I have this mentioned in my "how-to" thread, but I would like to post it here as well, if you don't mind TJ.
DBPowerAmp Music Converter:
http://www.dbpoweramp.com/dmc.htm
And...
All the audio conversion codecs you could need for it:
http://www.dbpoweramp.com/codec-central.htm
Using this program, you can convert to/from virtually ANY commonplace audio format - including the new lossless formats, change bitrates on MP3s, etc. VERY versitile program - I HIGHLY recommend having it installed with all the common plugins (Flac, Shn, MP3, MP3 (lame), Wav, etc). For those of you using the FLAC frontend - I would suggest perhaps trying this as an alternative. I've found it to be faster, more reliable, and (as hard as this is to believe) easier to use. You just select the files you want to convert... pick your output format... click convert - it couldn't be simpler.
That's just my opinion, but it's worth giving a looksee... This program CAN'T remain freeware for long - it's just too powerful and simple