Scratches is a new TextMate bundle that I'm finding very useful.
Basically it allows you to take snippets of code, "scratch" them, and then reuse them on other places. A sort-of glorified multi-buffer copy&paste. I believe the inspiration came from a BBEdit feature.
The Scratch bundle is still in the review section of the Macromates SVN. To install do:
cd ~/Library/Application\ Support/TextMate/Bundles
svn co http://macromates.com/svn/Bundles/trunk/Review/Bundles/Scratch.tmbundle
Tell TextMate to reload its bundles (menu Bundles > Bundle Editor > Reload Bundles) and you should be ready to use it.
The cool part is that this bundle was created in a couple of days in the TextMate mailing list. If you are curious, the threads starts here.