The first myth will be having to...
Warm Up The Engine Before You Drive
So the train of thought was brought about if you don't warm up the engine for about five minutes and begin to drive, the whole system will explode, killing you. Nah jokes, but seriously though...it will result in the car stalling and/or higher degradation of the inside of the automobile.
Yes it's true that the various components of the engine and oil do need a small bit of time to warm up so it can operate at maximum efficiency.
However, UNLESS you're flooring it everywhere you go like the hoon you are, there will be no problems with the car whatsoever. Starting the car in the morning, and driving off gently will allow the internals to warm up more quickly and efficiently than just letting the car warm up on it's own. Plus it's not a waste of fuel...
Let's think about it, if your car is idling it still produces power, so you may as well let that power be used to allow the car to move about.
On another note, there are other components of the car which requires warming up such as the wheel bearings and the transmission which won't get any heat if your car remains idle.
So in the end, you shouldn't really have to let your car warm up, as long as you keep rapid accelerations and high speeds to a minimum. Oh and this only applies to the modern, fuel injected cars. If you've got an an old 69' Charger, you'll probably have to stave off the road and chill in the parking area for a strong five minutes or so, while your car gets eye-humped by all the passer-bys. And also, if the temperature's gone to minus...just let it warm up for some peace of mind...
