Vibe Boost - An interactive digital museum of video-based art.
Wren - Offset your carbon footprint by saving rainforests
Mixergy - The YC Stories - How YC companies - Airbnb, Dropbox and more - Got Started
YAYZY - Track the carbon footprint of each purchase in real-time
Endangered Sounds Museum - Nostalgic sounds from the past
Capture - A great free screen capture utility that allows you to capture either a window or the desktop and save it to either a file or the clipboard.