ProTip is a peer to peer tipping for the web released under GNU General Public License. Earlier this year I took part in crowdfunding campaign to make this project happen. So far there is a chrome extension developed by Leo that you can try out. Currently Chris Ellis is running a NotJustMadeinChina campaign to provide more resources to develop a faucet feature and other things.
ProTip explained in pictures
ProTip is a peer to peer tipping for the web. It is implemented as a Chrome Extension.