Web Video Downloader can download .flv or .mp4 videos from various web sites.

Changes:

Now support VGA.
Fix little bugs for web site.
Add new tool bar.
Support alternative format on web site.
-Youtube (flv and mp4)
-bootyfix (flv and mp4)
-Tube8 (3gp and mp4)
Add a auto-update feature.

http://forum.xda-developers.com/showthread.php?t=427702