I have a 20' aluminum iMac (the one that came with a Mighty Mouse).
The not-so-mighty mouse started to fail, and I'm tired of trying to clean its wheel.
What's the best mouse that looks good with an iMac? It can be either Bluetooth, or USB (a short cord would be great).
My current choice is the Magic Mouse, but its lack of middle button, to open tabs in Safari, may be a deal breaker.
The Magic Mouse.
Coming from a Mighty Mouse you will probably miss the side buttons and middle click (who wouldn't), but you are getting gestures on your mouse and no scroll ball to screw up.
There are even some 3'rd party apps to add extra gestures, and you might even be able to get your middle click back :-)
I will answer here and not the topic mentionned by Dori because the OP specifically said "that looks good with an iMac?".
I'm using the Pro|Click mouse from Razer. Bought it a couple years ago. I fits nicely with the aluminium keyboard and iMac.
The photo I linked above gives you a more realistic feel for its color, it's not as white as the photos on Razer's site.
After two years use I can say I'm very happy with it. The fabric on the body is great, it's a little shiny and perfectly smooth. The wheel and sides give off a nice bluey light. Coincidentally I'm using the Creative Gigaworks T20 external speakers, which also have a bright blue led on the front. So in the evening, they go rather nicely together ;)
My only complaint is the fabric of the buttons. There are yellowish patches where I place my fingers. EDIT: Which can not be easily cleaned, I precise ;) Unfortunately because the buttons are made of a different type of plastic, slightly rubberish. Personally I don't understand why they use rubbery buttons like that, but it's not a big deal.
The mouse is also very good for gaming, which is something to consider if you have gaming sessions with bootcamp.
I'm not so sure about "looking good" but if you want a mouse that "works good" I'd suggest something that gives back some control over the acceleration of the cursor on the screen.
The Kensington Expert Mouse (yes, I know it's a trackball) Is I think one of the best options around. And as mentioned above it gives you fine control over acceleration.
