Just wanted to announce a TextMate plugin that I altered on github for easier file navigation.
When you open a folder in TextMate, a drawer with a navigator appears. The MissingDrawer plugin (https://github.com/jezdez/textmate-missingdrawer) promotes the drawer into a dedicated view that sits next to the text editor. You can show/hide the sidebar, and switch the sidebar's location also. Other commands are available in View > Project Drawer, and you can go to TextMate's preferences to customize colors and the Terminal button.
I wanted to be able to filter the files in my project based on name, similar to what is available in Xcode, for those of you who do Mac or iOS development. So I forked the project (https://github.com/legion80/textmate-missingdrawer-filter) and added a search widget at the bottom. Type in the search field, and it will immediately filter the list. You can jump to the search widget directly by using the ⌥⌘j shortcut (which is the same shortcut in Xcode 4).
To get the plugin, go to the project URL (https://github.com/legion80/textmate-missingdrawer-filter), and click on Downloads. Look for MissingDrawer-filter-0.4.0-0.1a.tmplugin.zip. Unzip the plugin, and double-click it. That should automatically install it.
You will only see the navigator if you are in a project, or opened a folder in TextMate.
I was only able to test this on OS X Lion, so let me know if you see any issues in Snow Leopard.
Enjoy, and be sure to file bugs in the github issues queue (https://github.com/legion80/textmate-missingdrawer-filter/issues)