"At more than one quadrillion floating point operations per second..." - how fast is that when cracking typical passwords or mining bitcoins? If we have an encrypted drive, how long would it take to find the passphrase with it?
As far as I know most passwords hashes are also integer operations.
The cell processor in the ps3, despite being optimized for floating point ops, can do about 22.23 Mh/s. Assuming each of the 12,960 PowerXCell 8is in Roadrunner can do the same: 12960 * 23.23 ~= 288100 Mh/s which would earn you about 21.6 BTC/day at the current difficulty. That's about $2000/day at current prices.
The PowerXCells also have 8 SPUs vs 6 in the ps3, so they are potentially 25% faster.