1)   YouTube Robot 6.0.2010
YouTube Robot lets you download video from YouTube.com onto your PC, convert it to various formats to watch it when you are on the road on mobile devices like mobile phone, iPod, iPhone, Pocket PC, PSP, or Zune. Support batch and schedule mode.

 2)   APPCRAFT YouTube Robot 3.0.708
Powerful tool that enables you to download, convert and transfer to mobile devices videos from YouTube and other similar websites.