Find in textmate
This is kind of a simplistic tip, but it's working great for me. I've been looking for a convenient way to do a Find In Project in Textmate for any files containing some text, but only for a subset of folders in my current project.
For example, when I create a textmate project for a Rails site, I drop the whole rails root into the side drawer, so I have ready access to everything, not just app/ but also config/, db/, spec/, etc. as well as any plugins (vendor/plugins/). I also like to freeze my rails core in vendor/rails/ (for various reasons mostly related to deployment) so that's also there under the textmate project.
All good, except when I need to search for files containing some text. I might only want to look in app/ or spec/, certainly not wait and clutter my search with results under all of vendor/.
I could just go into a shell and do a grep.
What I've come up with is to create separate textmate projects that contain only the subdirs I want to search in. So basically I have one project for the full rails root, one with just app/ and lib/, and one with spec/ and stories/.
A nice feature of textmate is when a file is modified in one project window, and you have the same file opened in another project window, they both will contain the same current content, even as you edit. So if you edit in one 'project', but save in another, it wont stomp all over your changes. Rather 'both' files get saved (since they're the same actually). That saves me a lot of heartache.