I've have this same issue, but it only happens to me about once every six months. I have no idea what it is. Ive tried to recreate the problem but can't. Its impossable to trouble shoot when you have no where to look. You may have better luck finding the problem because yours sounds like it happens more.
I know thats not really any help in solving the problem, but at least you know your not alone
Plus just to give someone more infomation that might have an idea as to what it is. I have an 04 Rubi, 63k it happens to be when I come to a stop (ie: stoplight or sign) it idles real rough, rpm drops, it has died and I've kept it running buy playing with the pedal. Happens quick and is over quick, if it dies it does start up again with no problem.