Nice 3 button mice?

oddly, the mouse that I've felt has the most compatible (and least obnoxious) styling in a room full of Macs was the Basic Optical from Microsoft. the third button is the scroll wheel but I think they are all like that now. I've placed many dozens of these in a few design and graphics companies. everyone was fine with them.

if you are looking for something more substantial, the Microsoft Intellimouse Explorer is bigger and has more buttons but is less attractive, and more expensive.

 

The Magic Mouse can do this, I've set up mine to do it, so in Safari, it opens links in a new tab. You'll need the BetterTouchTool app. It's a great app that lets you add custom gestures to your mouse, keyboard, trackpad and more.

I've made a short tutorial on it a few years back: http://forums.macrumors.com/threads/bettertouchtool-gestures.1693622/

 

Yes, there is a BetterTouchTool and there is MagicPrefs, which I honestly prefer after years of using both. You can set either the TrackPad or the MagicMouse to emulate the Middle-Button with a three-finger tap.