With the air conditioner on, my brakes don't work very well. Pretty frickin scary. When it first happened, I was backing out of a driveway. AC was on full blast. I stepped on the brakes and the car didn't stop but continued to roll. I panicked and really slammed on the brakes and it continued to roll. It finally came to a stop but not a hard stop. It took a matter of seconds to stop but if I could easily hit someone or something unintentionally. It happened a few more times before I took it to the dealership. I thought they were going to think I was crazy. You know how that goes, they probably wont experience it and I'm a woman. Luckily they were able to replicate the problem and they were the ones who told me it happens in drive too, but it isn't as significant as in reverse. Again, this only happens when the AC is on. MAKES NO SENSE!!! Today they are changing a "vacuum hose for the braking system" - whatever that is. I hope it fixes it. I'll keep you posted.

Update from Jul 24, 2013: My car was repaired! They replaced the booster vacuum pump switch. It shorted and was stuck open. Its been over a week and I haven't had the issue again.