The cost of an ASIC scrypt mining chip would be several times more than the cost of a SHA256 chip, that's why scrypt is used in the first place, so the coin you would have to mine would need to be several hundred percent more profitable than BTC to get the same ROI. Good luck! Keep dreaming.
They have mentioned plans to work on scrypt miner in the past haven't they? I don't know I could be wrong but I thought it was in the plans. A re-programmable fpga.