Thanks to the folks at AcademHack, I have been playing around with Evernote, a combination desktop/web tool for capturing and managing notes of all types. You can add tags (of course). You can search and collect all kinds of notes, pictures, sounds, etc. It can search for words within pictures.
The biggest thing for me, however, was watching the getting started video. As I watched it, I thought it would make a really interesting tool in the classroom for talking to students about collecting, categorizing, and retrieving information and materials.
Let me know what you think.