Patriot is soon going to release their new Patriot PDC22G10100ELK memory kit.
The product name of this memory kit is quite long and doesn't really tell a lot, but these Patriot modules promise a lot. They are supposed to be faster than the Corsair Dominator TWIN2X2048-1000C5DF memory kit which can do 1250MHz at 2.4V with 5-5-5-18 timings.
The new PDC22G10100ELK should be able to do 1262.5MHz with 5-5-5-18 timings at a voltage of 2.3V.
This kit should become one of the fastest DDR2 memory kits on the market, but according to HotHardware it won't be insanely expensive. You should be able to find the 2GB kit for $349-$399.