I love the Charlie Bag by Kwigy-Bo carrier I use for my boy. It actually looks like a Marc Jacobs handbag. I can open the side so he can poke his head out, or keep it closed. Its so discrete I even manage to sneak him on planes and avoid that 200 bill! Love it!!!
I bought my bag in NYC at trixie and peanut.. Here's a link to the Charlie bag::
Charlie Bag