Will MBA run when closed?

[Black]

Mr Downtown wrote:
I'm pondering the purchase of an MBA 11 to be my home computer, using an external keyboard and monitor. A product called BookArc makes it look like it's simple to run the MBA when it's closed (and improves performance), but an employee at the Apple Store this afternoon said the MBA goes to sleep when it's closed. Anyone know for sure? Does it matter which model MBA?

Bad bad "genius."
All recent Apple Laptops (since the Intels?) work flawlessly with the lid closed, given an external display, mouse and kb.
-start laptop
-close lid
. . .just like having a desktop from here on out.