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 just happen to 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 same 15% that restaurant staff expect as a minimum for dropping off a plate of food at your table in a warm restaurant, but at the pump just a loonie or twoonie from your parking change tray will usually get get a look of gratitude and a "thanks".
From time to time I've asked others if they do this, (including people I'm with who have no problem dropping that sort of change into a glass for someone who spent 5 seconds popping the cap off beer bottle for them), and I usually get 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 !
Winter tip: tip your gas jockey.