TextMate will not search binary files, granted it knows that the file type is binary. So right-click a file (using the extension you want to exclude) in the project drawer and select to treat it as binary.
Ah, excuse my laziness.
But just few little questions then: Is this exclusion list Project relative, or TM global? Is there a way to edit binary extensions (in Preferences like Folder references fields?) without using "Treat ..." for each of those? (probably I can do it with "defaults"?) How do I make folder with extension .pages or .drawit to be treated as single binary, though opened with double-click with associated app, and avoiding search to step into that folder too?
Thanks,