What bitrate do you encode your MP3's at?

Usually I go for v0's or 320 CBR. v0 tends to be my favorite because I cannot tell any difference in quality between v0 and 320, so I save a little room. I don't have the expensive equipment to hear the difference or the room to keep lossless so I convert everything to v0 unless I get it in 320, in which case I'll just keep it at that.

These days I rip to FLAC, but I have mp3s at 320, 192, 160 and 128. I enjoy them all, but I'm working on re-ripping all the old low-bitrate files. Disk is cheap these days.

Go for 320. At 320 the sound quality is very near-perfect. In ABX tests (google 'em) it is extremely difficult to choose between an mp3 and a lossless format (FLAC, WMA, etc.). While you may notice the most subtle of differences between them on high end audio, for most practical uses it makes very little difference, unless you're a sound engineer or well-seasoned audiophile.

128 is good enough for me. Anything above that is wasting space IMHO.

160.