I just submitted the following to commandlinefu :
Do you have a large library of flv’s you have picked up over the years using FlashGot Firefox plugin?
Do you want to be able to convert them to Ogg Theora (video) at once?
Try out this script…
for i in $(ls *.flv); do ffmpeg2theora -v 6 --optimize $i; done
Check it out and tell me what you think. Useful?