An update on the incremental-search plugin for NSTextViews that continues to be a big draw to this site - I don't currently use it on 10.5, since it's an input manager plugin, but I do miss it.
The most recent source that I know of is on leverage.sf.net which is a repository for text-system hacks I used to work on. If anyone wants to pick it up and modernize it, I'd be grateful.
In particular, you want the 'isim' directory. The other directories are unrelated, but if you find them interesting, I'd love to hear from you.
If you just want to download the last working universal binary build (from 2007), it is here: IncrementalSearchInputManager-universal.zip. Let me know how it works?