I apologise to your boss/spouse/significant other [delete as appropriate] in advance:
Wii Arcade - tons of addictive and rather cool-looking games here. Not from the Nintendo people, but all good fun. My fave? Bunker. You just kill everything.
Bloxorz - enjoyable, good looking puzzle game.
Crossword with a difference, no clues!
DrawPlay - help your little man get to the flag, by drawing his path with your mouse. It's better than it sounds, honest. And there's a funky soundtrack.