Moving Steam games from MBA to external USB 3.0 drive?

hi guys,

I just bought myself a 1TB USB 3.0 Touro external drive (7200RPM) and I'm wondering if it's possible to move my Steam games to the drive and run them from there?

I'm okay with keeping Steam on the MBA and just having it move the games over (and remember they're there in the future for updates and such), but if I'm better off moving the entire thing, that's no problem either. Whatever is better.

Anywho, can anyone point me in the right direction? My MBA only has 18GB left and it'd be really cool if I can just install all my future games (Steam or not... Diablo 3 for example) on the external and run them from there. I'm only limited to 5 games on this thing and I'd love to have more available.