Android/Windows: Pushbullet is easily one of our favourite cross-platform syncing tools, and today it gets a little better. Now the service includes universal copy and paste (if you use Android and Windows, of course).
To enable the feature, you'll have to go to the advanced settings on each device you want to sync. Once you turn it on, copying text on one device will automatically send it to the clipboard of all the others. The developers state they're working on adding iOS and OS X support, but for now it works pretty well between (you guessed it) Android and Windows devices.