Sun and IBM supercomputer pricing.

Pricing for the new IBM Blue gene/p is 10 to 15 cents per megaflop

This is $1.3 million for each of 13.6 teraflop racks of 32 processor boards in volume. $1.6 million in lower quantities.

216 of the racks is about $272 million for 2937 teraflops.

Sun’s Constellation in the 500 teraflop version costs US$29.6 million of a total $59 million to build Constellation, and $29.4 million for operational costs.
The full 1.7 petaflop version would probably cost $90 million to build.

So $50,000 to $100,000 per teraflop of supercomputer performance.

The Nvidia Tesla is in the range of $3000-6000 per teraflop.

FURTHER READING:
IBM and SUN announce petaflop supercomputers

Nvidia Tesla details

Nvidia tesla impact on computational chemistry

What it would take to reach a zettaflop