Sublime Text is very similar to TextMate, supporting many of the same keybindings, snippets, and themes. (I've even set up my system to use Ryan Bates's Railsca

Sublime Text is very similar to TextMate, supporting many of the same keybindings, snippets, and themes. (I've even set up my system to use Ryan Bates's Railscast theme to keep things looking familiar.) Unlike TextMate, Sublime Text supports multiple panes and is cross-platform. Because of its advantages (being cross-platform is the clincher), I'm planning to use Sublime Text in place of TextMate in the 2nd edition of the Rails Tutorial screencasts. I also hope to make a Sublime-specific screencast at some point, with an emphasis on keyboard shortcuts useful for Rails development. Further updates as events warrant.