It only snows / sleets / freezes 1-2 times a year here, so buying a car cover that protected against snow would be kind of a waste. I think car covers might scratch the paint. Also if its sleet / freezing rain then moisture will get through it then it'll just glue the cover to the car.

In for results.

DO NOT use WD-40.

That stuff is bad for anything plastic, i.e. all of that weather sealing around the windows/doors.

I second just using hot water much easier and you don't have to worry about tape residue being left on your car. I've had thick ice on my door before just kinda of used a little bit of force to pull them open

Please don't listen to the hot water on iced over glass advice. It can and will crack eventually. That's just plain physics.

Scraper in trunk is your best bet, as mentioned before. I've never had too much difficulty getting into the trunk, even with an inch of ice over it. Just have to be careful chipping the ice along the door seam below the glass, but there shouldn't be all that much ice there comparatively speaking.

Having lived in the frozen north, I was getting in and out of my car in -10* temps with the windows faulting only once so far. All this preparation is more work for no real results. I do give you credit for trying to be creative, though!

And as far as the ice, What I have done that works pretty well usually is find a part of the car (usually around the b-pillar, where the window meets it) and just hit it with medium force right along the pillar. There is enough flex in the car materials, but not the ice, so the car will flex under the ice, and the ice will crack, and you can start working at it from there. You won't break the glass unless you start whaling away with a hammer or other heavy object.

Side windows, at least in the US, are tempered glass and a lot more resistant to thermal shock. You want to avoid doing this on the windshield, however, as it is much more likely to fracture, especially if you use boiling water. If you read back, people are just recommending using "slightly warmer" water, which if you used 50-60* water, I doubt you will induce thermal shock.

Boiling water or not, it's dependent on the temperature difference. Enough temperature difference and even 'cold' water will crack glass. Granted, the glass would have to be really frickin' cold then ;)

Either way, if it ices over when you're out, ice scraper is still the answer :) Worst ice storm I've had to 'break' into the car with I was parked so far away at work, warm water wouldn't have survived sans a good thermos.

Well I don't pour hot water on the glass I pour it down the door jams usually for me anyway the rubber seals freeze on the inside of the door.

If your rubber seals are freezing you need to put silicone spray or shin etsu grease on them. They're dried out.

It's only happened after I go through a car wash or frozen rain and water freezes in the door jams its only happened twice tho

Semi-on topic, have any of you had the upper seal start to rub and end up getting pinched between the window and seal? I am guessing it just needs a little lube, but not sure what to use that wont end up streaking all over the glass.

I also use the prestone deice spray. Works great, and the can version comes with an integrated scraper.