Wren - Offset your carbon footprint by saving rainforests
Museum of Websites - Curated gallery of how internet companies changed over time
YAYZY - Track the carbon footprint of each purchase in real-time
Vibe Boost - An interactive digital museum of video-based art.
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.
Endangered Sounds Museum - Nostalgic sounds from the past