FLOPS (floating point operations per second) are one way of measuring raw computing power.
Techreport has a review of a three-way SLI graphics card system. This system has 1.7 teraflops just in the graphics subsystem, not counting the CPU. This configuration would cost around $2,000 just for the graphics cards. A lot for a PC these days, but peanuts compared to the old days.
According to Wikipedia, in 1961, a single FLOP would cost you over $1,000. As recently as 2000, a $1,000 buys you a gigaflop; a billion-fold increase in cost efficiency.
With Moore's Law alive and well, who can tell what the future will bring.