I've been using it for 3 years now, but keep forgetting to tell anyone about it. It's a simple bash script that detects what kind of project your current directory is and runs the appropriate command to start the development server.

I created it, because I found myself constantly switching between projects of different types, and it always took me a few moments to remember if the current project was Rails 2 or Rails 3/4, Node, Jekyll, Rack app, etc. and starting the development server on port 3000 was starting to take 2 or 3 tries before getting it right.

Now, I just cd into any project and run `start`. It currently detects Foreman projects, Rails (old and new), Jekyll (old and new), Gollum, plain Rack apps, and Node; and it's easy to add new things as well.