Two of the industries most interesting processors, AMD's server-class "Opteron" and the notorious "Cell" CPU, are becoming paired together in a strange mix of technologies. IBM recently won a bid to build a supercomputer that will utilize both processors, supposedly achieving a calculation rate of 1 Petaflop. Dubbed "Roadrunner", the machine is being built for the Los Alamos National Labratory at a cost of around $35 Million. While the official word from them hasn't yet been heard, there are already rumored finish dates:

Now sources familiar with the machine have said that IBM has won the contract and that the National Nuclear Security Administration is expected to announce the deal in coming days. The system is expected to be built in phases, beginning in September and finishing by 2007 if the government chooses [to] build the full petaflop system.
Neither IBM or LANL have commented on the pending deal. The mere idea of a such a beast raises a lot of questions, such as the technology behind bringing two different architectures together. IBM has introduced such technology on a smaller scale in their blades, as the article brings out. The decision to use the two technologies is partly based in power demands.