Saw some automotive flares sitting on the shelf at TrueValue. Reminded me of watching the
http://en.wikipedia.org/wiki/James_Kim#Snowbound Kati Kim story. The husband, wife and child were stranded in their vehicle in the snow for ~8 days. At one point she said her husband removed the spare tire and planned to burn it to signal for help.
At some point they heard a helicopter or airplane close by. He went to set the tire on fire using kindling (including his daughters stuffed animal) but couldn't get a good fire going good enough in the snow to get the tire to catch fire. Needless to say the aircraft left and wasn't heard from again. The story ends in the husband trying to walk to get help and dies. Wife and child picked up about a day later when spotted by helicopters. I think about 7 days after they tried to signal the first one.
Now from my dad letting me have ones that were old to play with as a kid, I know they burn really hot, very visible, and can melt through chain link fencing

. I already had large glowsticks in our vehicles for signaling, but no flares. I picked up 3 for each vehicle. Maybe if I ever need to get a fire/tire burning quickly, the flares will accomplish the job.