Some pictures of a four-way CrossFireX system have appeared on a Chinese blog and the rig apparently contains an RD790FX board and a Phenom processor of unknown speed and model.
This is apparently AMD's upcoming Spider platform and it's meant to take on Nvidia's three-way SLI platform based on the 780 chipset for either Intel or AMD processors.
The pictured system contains four Radeon HD 3850 cards and it should be possible to fit three other expansion cards into the system due to the single slot nature of the 3850s.
There's also a picture of a 3870 card in a different machine. The quality of the pictures look as if they've been taken with a camera phone, but they're clear enough to at least show some detail.
You can find the pictures
here