Localbuilder is a simple solution to local Continuous Integration as well as being useful for a few other common tasks 
during development. It's written in Python but could be used on projects using any language.

./localbuilder --path /path/to/watch --command /command/to/execute

You can also specify the time between checks with the --period option. This defaults to 60 seconds.

Basic usage involves setting it to watch your working project folder. Whenever you make changes to any of the files, 
localbuilder will execute the specified command. Personally I use this mainly to execute a unit test suite whenever I 
make changes to a project.