Here's BFL's
latest video, showing a 5 GH/s miner in what is suspiciously not a Jalapeno case. The power consumption isn't as bad as what their apparent first attempts were getting, though.
From what I see in the video it's 36 Watt.
So:
Jalapeno (5 GH/s): 36 Watt
Little Single (30 GH/s): 216 Watt
216 Watt is roughly what the cooler of a 7970 GPU has to dissipate.
Now look at the cooling solutions: