WebKit

WebKit is a Open Source rendering engine.
It is very Fast.
http://en.wikipedia.org/wiki/Webkit

It is, for example, used in Google Chrome:
http://en.wikipedia.org/wiki/Google_Chrome
http://www.google.com/googlebooks/chrome/images/big/12.jpg

At MobiNear, we use the WebKit (Open Source) in all our TouchScreen Kiosks
(i.e. MobiNear Box Touch)