A GTX 660 should be good for >180 kHash with the new cudaminer:
https://bitcointalk.org/index.php?topic=167229.0See the Google doc linked in that post for some custom tweaking settings.
I think you already have the CPU mining thing figured out - use your CPUs on coins that GPU, FPGA, and ASIC are
not good at. No one knows which one of the CPU only coins will survive, and just like Scrypt coins I'm sure the most profitable coin bounces around every hour. (I'm sure a bunch of people are running scripts that change what their CPU is pointed at depending on profit calculators, similar to the auto-switch scrypt pools.)
I'm personally using my CPUs on World Community Grid for the Ripple Labs XRP giveaway - probably not as profitable as CPU coins but more useful use of compute in my mind + the BOINC client is more reliable than any miner out there.