This application server a very clear purpose: convert Youtube videos to formats compatible with mobile devices like an iPod or a mobile phone. It's really easy to use and requires no technical knowlede: just copy and paste the video URL into its interface and click on the "Download and Convert" button.

You have several presets from which to choose the target device and the desired quality level for the converted file, but no possibility to tweak these options manually. The program works well and is completely free, although in exchange for that you're obliged to see a pop-up every time you open it or complete a conversion.