Feature Request: Horizontal two finger scroll to go forward an back

The title says it all, i think it would be great if you could use the trackpad to go forward and back when browsing the web. The enhancement would look something like this:

if the web page you are on does not have a horizontal scroll bar, use two finger trackpad input in a horizontal motion to control scrolling forward and back. If the page does have a horizontal scroll bar, click Command while scrolling horizontal to control forward and back.

What do you think?