friedcat seem to be the cheapest currently. But requires some DIY from what i can see.
Alternative if you want a hitnrun go with the S3.
However.. ROI is unlikely at the current btc price, so you'll have to hope for a rise in value.
ASICminers stuff doesn't use "normal" mining software,I'm not too keen on them for that reason,it's a bit involved in getting it to mine & only at certain pools
![Roll Eyes](https://bitcointalk.org/Smileys/default/rolleyes.gif)
S3's seem the only decent choice ATM......easy to setup,decent power consumption,ok price.........
With ya on the ROI thing mazedk,just hold your mined BTC
![Wink](https://bitcointalk.org/Smileys/default/wink.gif)
Personally hoping BTC hits $100 for 6 months..........weed out the farms........maybe
![Cheesy](https://bitcointalk.org/Smileys/default/cheesy.gif)