In cold weather like this nothing sucks more than filling your car with gas. I don't seek out stations with gas jockeys but a couple of the places I frequent the most out of convenience have them.
I'm not the world's greatest tipper but I do try to leave something with the guy (or gal) for doing this most miserable winter job. Now, I'm not talking the 15% that restaurant staff expect as a minimum for dropping off a plate of food at your table in a warm restaurant, but just a twoonie will usually get get a look of gratitude and a "thanks".
From time to time I've asked others if they do this, (including those that have no problem leaving a couple of bucks at the bar for someone who spent 8 seconds popping the caps off a pair of beer bottles), and it usually draws a quizzical look.
Seriously, folks. If there's ever a job that cried out for a tip it's the gas jockey stuck outside for most of an eight hour shift breathing in petrol fumes while doing a job that you're not willing to do yourself !