http://www.wunderlist.com/
Funky open source web app around task management that syncs and has a client across Mac, Win, iPhone, Android. Apparently no linux support. Built on top of Titanium from appcelerator.
http://www.appcelerator.com/
Incredibly interesting app development platform that builds apps for all platforms (desktop & mobile, including linux, yay!) quickly with a single API. Open source, free, pay for premium support. Very, very interesting business.
