I'd highly recommend you all secure historious.com while you still can get it at a decent price (read: before you get funding, big name recognition, etc). While domain hacks are cheap and cool in the startup world, they confuse average people like our parents and neighbors.

The potential for confusion is one of the reasons that Yahoo forked over big bucks to buy delicious.com and redirect del.icio.us there. Even if you wanted to keep your domain hack, you could always point the .com version to your domain hack. It sure beats letting someone else show ads and confuse customers to where they think you've gone out of business.