UI

Beginners Guide to learn UX design

It's one of the best, even better than photoshop, used by professionals, and has a good community.

Just call C++ from C#.

Speed up, slow down, advance and rewind HTML5 audio/video with shortcuts.

Far and away the best solution I've found for keeping my desktop wallpaper fresh on Linux; the quotations feature really adds a ton of utility, especially if you stick to a small rotation of images.

Large, well established framework with huge community

Very simple, just what you need.