I can set one up but the issue is the monetary funding and distributing the btc.
Microwallet is the best service -or- Coinbase.
I think bitpay offers something if you contact them (as well).
Monetary funding! You could put $5 of btc in a faucet and it would last for ages (Thats like 806,000 satoshi?) If you gave out 200 satoshi dispenses thats over 4,000 dispenses right there. Ad space would more than cover the cost of 4,000 dispenses...
And microwallet is by far the best, people get paid instantly with no transaction fee's