Adam Savage of MythBusters fame chimes in on an AskMetaFilter question: How long in the freezer to chill a Coke from 89F to 35F?
This is particularly interesting to me, as we've had more than one freezer disaster at Chez Kev.
That would be about 20-25 minutes in a freezer. If you put it in a bucket of ice, that would halve that time. If you put water in that ice, it'd be cold (+- 5c) enough to drink in about 4-6 minutes, if you put salt in that water, you'd reduce the chill time to just over 2 minutes. Agitating the can in the water, rolling it around, reduces the chill time even more.
The fastest possible way is to grab a CO2 fire extinguisher and unload that sucker on the can.
As G.I. Joe says – knowing is half the battle. 🙂