found this gem about PANDA profitability
Quote
Network hashrate = D * 2^32 / BT
D (Diff) is 150.
BT (block time in s) is 150.
so Network hashrate ~= 4.3GH/s.
With 500KH/s, which is equivalent to 1 MH/s for traditional scrypt coins, you have 0.01164%...