diff --git a/CHANGELOG.rdoc b/CHANGELOG.rdoc
index 5fa001b..34290c0 100644
--- a/CHANGELOG.rdoc
+++ b/CHANGELOG.rdoc
@@ -1,3 +1,7 @@
+== 0.3.0 / June 2nd, 2009
+
+* Added ability to set variables on the fly from the command line (ex: whenever --set environment=staging). [Javan Makhmali]
+
 == 0.2.2 / April 30th, 2009
 
 * Days of week jobs can now accept an :at directive (ex: every :monday, :at => '5pm'). [David Eisinger]
diff --git a/Manifest b/Manifest
index f256704..954fe50 100644
--- a/Manifest
+++ b/Manifest
@@ -10,6 +10,7 @@ lib/job_types/runner.rb
 lib/outputs/cron.rb
 lib/version.rb
 lib/whenever.rb
+Manifest
 Rakefile
 README.rdoc
 test/command_line_test.rb
@@ -20,4 +21,3 @@ test/output_rake_test.rb
 test/output_runner_test.rb
 test/test_helper.rb
 whenever.gemspec
-Manifest
diff --git a/bin/whenever b/bin/whenever
index 6c761cc..39993f4 100644
--- a/bin/whenever
+++ b/bin/whenever
@@ -24,6 +24,9 @@ OptionParser.new do |opts|
   opts.on('-u', '--user [user]', 'Default: current user') do |user| 
     options[:user] = user if user
   end
+  opts.on('-s', '--set [variables]', 'Example: --set environment=staging&path=/my/sweet/path') do |set|
+    options[:set] = set if set
+  end
 end.parse!
 
 Whenever::CommandLine.execute(options)
\ No newline at end of file
diff --git a/lib/command_line.rb b/lib/command_line.rb
index d7920a8..b1bad31 100644
--- a/lib/command_line.rb
+++ b/lib/command_line.rb
@@ -28,7 +28,7 @@ module Whenever
       elsif @options[:write]
         write_crontab(whenever_cron)
       else
-        puts Whenever.cron(:file => @options[:file])
+        puts Whenever.cron(@options)
         exit
       end
     end
@@ -40,7 +40,7 @@ module Whenever
     end
   
     def whenever_cron
-      @whenever_cron ||= [comment_open, Whenever.cron(:file => @options[:file]), comment_close].join("\n")
+      @whenever_cron ||= [comment_open, Whenever.cron(@options), comment_close].join("\n")
     end
     
     def read_crontab
diff --git a/lib/job_list.rb b/lib/job_list.rb
index 21a799f..245d7b8 100644
--- a/lib/job_list.rb
+++ b/lib/job_list.rb
@@ -5,20 +5,24 @@ module Whenever
       @jobs = Hash.new
       @env  = Hash.new
       
-      config = case options
-        when String then options
+      case options
+        when String
+          config = options
         when Hash
-          if options[:string]
+          config = if options[:string]
             options[:string]
           elsif options[:file]
             File.read(options[:file])
           end
+          pre_set(options[:set])
       end
 
       eval(config)
     end
     
     def set(variable, value)
+      return if instance_variable_defined?("@#{variable}".to_sym)
+      
       instance_variable_set("@#{variable}".to_sym, value)
       self.class.send(:attr_reader, variable.to_sym)
     end
@@ -57,6 +61,20 @@ module Whenever
     end
     
   private
+    
+    # Takes a string like: "variable1=something&variable2=somethingelse"
+    # and breaks it into variable/value pairs. Used for setting variables at runtime from the command line.
+    # Only works for setting values as strings.
+    def pre_set(variable_string = nil)
+      return if variable_string.blank?
+      
+      pairs = variable_string.split('&')
+      pairs.each do |pair|
+        next unless pair.index('=')
+        variable, value = *pair.split('=')
+        set(variable.strip, value.strip) unless variable.blank? || value.blank?
+      end
+    end
   
     def environment_variables
       return if @env.empty?
diff --git a/lib/version.rb b/lib/version.rb
index 4a9c456..a020f59 100644
--- a/lib/version.rb
+++ b/lib/version.rb
@@ -1,8 +1,8 @@
 module Whenever
   module VERSION #:nodoc:
     MAJOR = 0
-    MINOR = 2
-    TINY  = 2
+    MINOR = 3
+    TINY  = 0
 
     STRING = [MAJOR, MINOR, TINY].join('.')
   end
diff --git a/test/output_command_test.rb b/test/output_command_test.rb
index 413d5be..ff9005c 100644
--- a/test/output_command_test.rb
+++ b/test/output_command_test.rb
@@ -67,4 +67,21 @@ class OutputCommandTest < Test::Unit::TestCase
     end
   end
   
+  context "A command when the cron_log is set and is overridden by the :set option" do
+    setup do
+      @output = Whenever.cron :set => 'cron_log=otherlog.log', :string => \
+      <<-file
+        set :cron_log, 'logfile.log'
+        every 2.hours do
+          command "blahblah"
+        end
+      file
+    end
+
+    should "output the otherlog.log as the log file" do
+      assert_no_match /.+ .+ .+ .+ blahblah >> logfile.log 2>&1/, @output
+      assert_match /^.+ .+ .+ .+ blahblah >> otherlog.log 2>&1/, @output
+    end
+  end
+  
 end
\ No newline at end of file
diff --git a/test/output_runner_test.rb b/test/output_runner_test.rb
index 70dfbd6..0142852 100644
--- a/test/output_runner_test.rb
+++ b/test/output_runner_test.rb
@@ -122,4 +122,72 @@ class OutputRunnerTest < Test::Unit::TestCase
     end
   end
   
+  context "A runner where the environment is overridden using the :set option" do
+    setup do
+      @output = Whenever.cron :set => 'environment=serious', :string => \
+      <<-file
+        set :environment, :silly
+        set :path, '/my/path'
+        every 2.hours do
+          runner "blahblah"
+        end
+      file
+    end
+    
+    should "output the runner using the override environment" do
+      assert_match two_hours + ' /my/path/script/runner -e serious "blahblah"', @output
+    end
+  end
+  
+  context "A runner where the environment and path are overridden using the :set option" do
+    setup do
+      @output = Whenever.cron :set => 'environment=serious&path=/serious/path', :string => \
+      <<-file
+        set :environment, :silly
+        set :path, '/silly/path'
+        every 2.hours do
+          runner "blahblah"
+        end
+      file
+    end
+    
+    should "output the runner using the overridden path and environment" do
+      assert_match two_hours + ' /serious/path/script/runner -e serious "blahblah"', @output
+    end
+  end
+  
+  context "A runner where the environment and path are overridden using the :set option with spaces in the string" do
+    setup do
+      @output = Whenever.cron :set => ' environment = serious&  path =/serious/path', :string => \
+      <<-file
+        set :environment, :silly
+        set :path, '/silly/path'
+        every 2.hours do
+          runner "blahblah"
+        end
+      file
+    end
+    
+    should "output the runner using the overridden path and environment" do
+      assert_match two_hours + ' /serious/path/script/runner -e serious "blahblah"', @output
+    end
+  end
+  
+  context "A runner where the environment is overridden using the :set option but no value is given" do
+    setup do
+      @output = Whenever.cron :set => ' environment=', :string => \
+      <<-file
+        set :environment, :silly
+        set :path, '/silly/path'
+        every 2.hours do
+          runner "blahblah"
+        end
+      file
+    end
+    
+    should "output the runner using the original environmnet" do
+      assert_match two_hours + ' /silly/path/script/runner -e silly "blahblah"', @output
+    end
+  end
+  
 end
\ No newline at end of file
diff --git a/whenever.gemspec b/whenever.gemspec
index 66d8828..71ce5e0 100644
--- a/whenever.gemspec
+++ b/whenever.gemspec
@@ -2,16 +2,16 @@
 
 Gem::Specification.new do |s|
   s.name = %q{whenever}
-  s.version = "0.2.2"
+  s.version = "0.3.0"
 
   s.required_rubygems_version = Gem::Requirement.new(">= 1.2") if s.respond_to? :required_rubygems_version=
   s.authors = ["Javan Makhmali"]
-  s.date = %q{2009-04-30}
+  s.date = %q{2009-06-02}
   s.description = %q{Provides clean ruby syntax for defining messy cron jobs and running them Whenever.}
   s.email = %q{javan@javan.us}
   s.executables = ["whenever", "wheneverize"]
   s.extra_rdoc_files = ["bin/whenever", "bin/wheneverize", "CHANGELOG.rdoc", "lib/base.rb", "lib/command_line.rb", "lib/job_list.rb", "lib/job_types/default.rb", "lib/job_types/rake_task.rb", "lib/job_types/runner.rb", "lib/outputs/cron.rb", "lib/version.rb", "lib/whenever.rb", "README.rdoc"]
-  s.files = ["bin/whenever", "bin/wheneverize", "CHANGELOG.rdoc", "lib/base.rb", "lib/command_line.rb", "lib/job_list.rb", "lib/job_types/default.rb", "lib/job_types/rake_task.rb", "lib/job_types/runner.rb", "lib/outputs/cron.rb", "lib/version.rb", "lib/whenever.rb", "Rakefile", "README.rdoc", "test/command_line_test.rb", "test/cron_test.rb", "test/output_command_test.rb", "test/output_env_test.rb", "test/output_rake_test.rb", "test/output_runner_test.rb", "test/test_helper.rb", "whenever.gemspec", "Manifest"]
+  s.files = ["bin/whenever", "bin/wheneverize", "CHANGELOG.rdoc", "lib/base.rb", "lib/command_line.rb", "lib/job_list.rb", "lib/job_types/default.rb", "lib/job_types/rake_task.rb", "lib/job_types/runner.rb", "lib/outputs/cron.rb", "lib/version.rb", "lib/whenever.rb", "Manifest", "Rakefile", "README.rdoc", "test/command_line_test.rb", "test/cron_test.rb", "test/output_command_test.rb", "test/output_env_test.rb", "test/output_rake_test.rb", "test/output_runner_test.rb", "test/test_helper.rb", "whenever.gemspec"]
   s.has_rdoc = true
   s.homepage = %q{http://github.com/javan/whenever}
   s.rdoc_options = ["--line-numbers", "--inline-source", "--title", "Whenever", "--main", "README.rdoc"]