Comment 59 for bug 147230

@ robert: since I guess you used heavily this feature while using a mouse
(on a laptop it was really unbearable), I suggest a solution which might be even better
than the old behaviour: if your mouse has "horizontal scroll" by tiltable scroll-wheel
(most of recent Logitech mice, for example, have it), you can bind "Button6" and "Button7"
to viewport switching. This way, you don't even need to have some desktop exposed,
you can flip viewports lightning-quickly.
Since I think the horizontal scroll feature is generally not very useful, I wonder wheter
this behaviour could be even be enabled by default....