Bitcoin uses double SHA256 which is all integer operations, so that's not directly comparable to flops.

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.