Nimbus Screenshot - Take screenshots and record video from your screen
Visual Beat - Interactive music video
Evernote Web Clipper - Clip, don't bookmark. Web Clipper is a browser extension that lets you save any web page, article, or image into Evernote. Download now.
The Lucid Realm - Listen to music in 3D
ksnip - Ksnip is a Qt based cross-platform screenshot tool that provides many annotation features for your screenshots. - DamirPorobic/ksnip
Google Music Lab - Interactive experiments that use the Web Audio API