USB Media Card Reader

I have an Asus Transformer TF-101 with a Keyboard.

The keyboard as you know has two USB connections.

I am looking for a Media card reader which will plug into one of the USB connections and work with Andriod. It must read Compact Flash cards.

I have tried a few with no success as they use either Windows or OS drivers:(.

Does anyone know if there is a card reader like this that works with Android and where I can obtain one in the UK?

Many thanks.