I don't mind the electrical usage where my main miner is but what gets me is the nightly AC shutoff.  I'm struggling to keep it stable at night now that summer is starting.

I agree. I just got into mining, and I even upgraded the GPU in my PC to a 7970 with the intent of mining faster than my GTX 670 could do. However, I didn't buy the card (nor assemble the computer) for the sole purpose of mining, and at the end of the day, I have a badass gaming rig that I can play any game maxed out, which is why I built my rig in the first place. I'm not worried about making my investment back, so long as I don't spend more on electricity than I make mining, which I am currently doing pretty good at (700 MH/s).  That and the 7970 came with 3 games that I had really been wanting to play.