I bought a Philips BDP3000 which I only found out much later could be changed to play Region A discs by altering the firmware update before installing it. You can find out how on youtube. The great thing is, you can pick it up for around £50 delivered, refurbished of course, but I've never had any problem with refurbished.
Once it's hacked, it is basically a Region A player, but will obviously play region free. I don't know if it can be changed back, but I'd imagine it would with another firmware.
It's a great player too. My PS3 has now become my second player, for Region B locked only.