Xilisoft iPod Video Converter
It does a great job of converting just about any file format you can name to a format that can be viewed on your iPod, including AVI, MPEG, WMV, MOV, RM, RMVB, DivX, ASF, VOB, and 3GP. It can also convert audio files to iPod-friendly formats as well, including these: WAV, WMA, MP2, AC3, RA, OGG, CDA, APE to iPod MP3, M4A, AAC.
As a nice plus, it supports the latest iPod specs of MPEG-4 video at 640 by 480 resolution. The program does more as well, including ripping CDs. It's shareware, and costs $29 to register. --Preston Gralla