I've tried Logmein Ignition, splashtop Remote and Android VNC Viewer.
Logmein works, its controls are a bit cumbersome... and so is the price.
Splashtop remote just came out, and is fairly buggy. Some promised features are not present/working. Lower price, but who knows if it will ever work correctly
Android VNC, works fine, but requires advanced knowledge of networking to setup. Not nearly as easy and convient as Wyse's Pocketcloud.
PocketCloud - Easy to setup, secure, and gives every feature you would expect of being at the computer. Sound, Keyboard, Scrolling, Clicking, ALT, Control, F1 keys, etc! Like your computer is really in your hand