@jorgy: Yeah, I really liked the concept of Reduced Instruction Set Computer. But Intel has some smart technologies to overcome the drawbacks of CISC (typically: X86). Luckily IBM keeps developing the RISC technology for portables and game consoles, and perhaps will see a revival of RISC in the desktop computer market at some point in the future. Who knows, perhaps computer based on fotons instead of electrons can do just that.
Anyway, AFAIK the fastest computer at this moment are the Cray supercomputers, which use AMD Opterons for parallel computing. The Cray X1E Supercomputer retails at roughly 10 million USD. Of course, Cray has entry level models for 100,000 USD. Anyways, that is far above my budget (around 1000 USD for a replacement computer, I guess).
In earlier models Cray used the SPARC (64 parallel) in their Cray S-MP, but nowadays they have chosen for the AMD Opterons

I think Intel's Duo Core is a superior processor to the AMD Opteron.
And there is, of course, the myth of the quantum computer (only a theory, no practical applications expected within the next 15 years) which has no speed limits and should have an infinite computing power. This power is necessary for building a possible time machine (which is theoretically possible, but a bit impracticle at the moment, because you'll probably need roughly the mass of the milky way to power it). Unfortunately, you can only use such a time machine when it physically exists, so you cannot go back in time before the time machine existed and no further in the future than the lifespan of the time machine—a time machine is a transporter, not a vehicle; it transports matter across time-space.
So, that might be something for Lucky Bob to consider the next time he flashes through time-space
