Sparrowhyperion:
There is another option I have been trying out lately and it seems to work. Decant and use your favorite rattle can paint. Just get an empty jar (I use empty baby food jars), stretch some plastic wrap over the top and poke a small hole in it. Stick the cans spray head in and spray until the can is dead. Make sure to try and hold the can as upright as possible so you get as much paint out as you can. One of the benefits is that the can paint is already thinned to the correct consistency or at least very close, so you usually do not need to thin it further. I find it cheaper than using the jars unless you need to use some color that doesn't come in a rattle can.
Learn something new everything day. I heard people decant when they cannot find the exact color in bottle. Now, it adds the economic factor.
Take Tamiya paints as an example. Usually, a 3-oz spray can costs $6 plus and a 3/4-oz bottle paint $3 minus.
You get 1.5 oz of paint for about $6 in bottle. You usually thin it to about 3 oz or more for airbrush.
How much paint can you recover from the $6 spray can to justify the trouble and cost of decanting?