KNC Jupiter is the best GH/s/$ return right now
One doing really well is https://bitcointalksearch.org/topic/m.2577450
Then you would be mining with one of the most competitive mining technologies available 24/7
Still, it's cheaper than the official price by KNC...
here's some pointers:
1. get in touch with Derek from http://sgminingconsortium.wordpress.com/
2. I'm selling a BFL 5 Gh/s jalapeno (in-hand today Friday or next Monday. The postman is slow. PM me for the price.