Up to $2.699 here in Minneapolis, paid $3.299 for 93 octane at BP today. Even though I can't charge the Volt right now (needs the battery module and hybrid module reprogrammed due to an erroneous "loss of isolation" code), it still doesn't cost me much. It's a 9 gallon tank and get's ~35 MPG, so I'm filling up for round about $25 even at those prices. I commute ~15 miles a day, and get about 260 miles out of a tank, so I get about 2 weeks out of a tank assuming I don't go anywhere else. Real world, I get about a week per $20. When I was running on full electric, it cost me about $65 a month in utility charges, so I'm not losing much.
EDIT: just realized I posted in this thread this past Sunday and said regular was $2.399. Wow, kind of puts it in perspective. 30 cent rise in 3 days?? That doesn't even account for the impending switch to summer blend. This may get rowdy soon...