Winter is the only time that I ride with puncture-resistant tire liners AND slime in my tubes at the same time, re-lube my chain at least once per week (more often if the chain gets wet). I also try to give the bike a good looking over for other things once a week.
In the rare event that I do get a flat tire, slimed tubes usually allow me to just pump up the tire enough to get to a warmer place to patch/fix the tube (home, work, local fire station or garage, etc.).