You have got to see this! Asus has nearly completed their dual-7800 GT card and is nearly ready to ship! This card features not one, but TWO 7800 GT cores on a single card, running at 489 MHz core and 1.358 GHz memory clocks! I have included some more pictures below!!
It does use an external power supply but that might actually be a good idea as power requirements on the PSU will go down because of it. Here is a thread in our forums to discuss this new technology.