Comment 12 for bug 710762

Editing xorg.conf should really never be the only solution for such a rudimentary accessibility feature. As #6 and #11 point out, there are actually a lot of two-button mice out there; on nearly every laptop and netbook sold the past 15 years the track-pad includes only a left and a right mouse button.

In addition to the Unity functionality mentioned above, the middle mouse button also functions as the paste action for selected text; this is often very useful in a terminal where ctrl+c ctrl+v does not work (which is what bit me just now, making me wonder what changed). It would be nice if an option could be added to the mouse configuration tool to allow middle mouse button emulation.

If this only affected a few mice I would agree with Bryce's WONTFIX, but there are millions of built-in two-button track-pad mice out there. I think "quite rare" is a bit of an understatement.