Any way to rebind the free camera control button?

[petemyster]

Is there any way to bind this function to a different key. Incase I didn't make it clear what I'm talking about, its when you hold in the middle mouse button and it lets you position the camera to your liking. But there is no key binding option for it in the options menu.

As my middle mouse button is broke on my mouse, I'd like to change it to a different button. But without it appearing in the options I have no way of doing this. Any ideas?