I'd just go with whatever Logitech Optical mouse you can get for 20 bucks. I just bought one for that price and it's nice. They have some lines that are ambidextrous, though their higher-end mice aren't. You won't get 5 buttons, though.

Mouse recommendation: don't throw it on the fire.

Lessons learned, dodgy?

This one looks nice.

I'm not going to be able to talk you into switching to a trackball, am I?

dodgygeezer wins! Or, rather beat me to it. I actually dislike the idea of winning threads but I digress....

Why should I? I've thought about it in the past. How will it affect my gaming? And I'm pretty sure my guests will complain they don't know how to use it. Plus, a trackball takes up a certain amount of space, and I sometimes like to be able to mouse on odd surfaces (ie while standing up and talking on a phone). I should probably cave and go wireless for the mobility thing; I'll have to see what Staples has.

I really dig my Apple Mighty Mouse (which works with Win XP), but alas, it is more than double your price range.

I have a Logitech scroll wheel, dual laser mouse that is nice. But I don't think they make it any more. Really, there is not all that much difference in the super cheap range: just run to CompUSA or whatever and grab what feels best in that price range.

why, Mickey of course!

If you play a lot of Centipede and Marble Madness, it'll probably affect your gaming positively. If you play a lot of FPS's, probably negatively (I gather that plenty of people like 'em just fine for those kinds of games, but it seems like a minority). I find it less stressful (hand motion vs wrist/arm motion). There's no reason you can't use a trackball on odd surfaces just as successfully as a mouse, if not even more so. If you're a big gamer, though, a trackball might not be the right choice for you (and if you'd like to make things easier for guests and whatnot, it probably isn't).

Eidetaker, I've got a battery-less wireless mouse from A4 that I really like. It was about $25 or so from CyberGuys. Its sweet because its light, lights up and works well. But it can't be used without the included mousepad as that's how it gets power.

And, if you've got a toddler, be prepared to go searching for it every so often as my little boy loves to grab Daddy's mouse and run away with it, laughing maniacally.

sorry Eideteker, not taker. Dizaaang!

It's a pain to buy a comfortable mouse as a lefty (I am too).

Definitely consider wireless! It's so much nicer without a wire. I have this (wireless) mouse from Logitech. Froogle says you can get it for less than 20 buck buck bucks.

I had this (corded) Logitech mouse before (but it broke).