I use a FTDI interface to talk to my Ardweeny, and I can turn it into a USB host? If I could wire one of those guys onto my project and use it as a host controller, I'd be pretty happy with the solution. Granted, it's not the cheapest way to go, and it's still pretty big, but it would get the job done using hardware that I'm already familiar with. It'll be a pain to connect it to my project board, but I'll manage.
Thanks...