Interesting aside "natural selection".
Going back for a bit. I've been sticking to urban sounds. Automated announcements and prerecorded voices. For reasonable quality I use a mini disk, but more recently i've been using my iPhone . Low quality isn't a problem if you plan to mangle the sound you're recording and I like the fact I can e-mail the recordings to myself with a note saying what they are.
a friend of mine has been recording w/his iPhone too. and yeah, urban announcement and broadcast is one of the best textures.