I'm currently using the old Apple Mighty Mouse and I configured clicking on the trackball as a "middle click" that's been very handy for opening links in new tabs, closing tabs, etc. However, the mouse is starting to show its age and I've been looking at Apple's Magic Mouse and Magic Trackpad, and I'm wondering - do either of these support the "middle click" operation? If not, is there a gesture or a multi-finger click that can be used for the same things (i.e. opening new tabs, etc)?
Multitouch is another option for adding "middle click" functionality to the Magic Mouse.
(Disclaimer, I'm the developer.)
Middle Click is a free app and is perfect for that.