FRETS.COM
Shop Tip #288
© Frank Ford 2006; Photo by FF

I keep a few old cans around for times when I might be working with hot liquids, but otherwise, I've pretty much quit saving them.  Instead, I have stacks of plastic yogurt and cottage cheese containers - they're just as good for paint, glue or solvents, and unlike cans, they stack tightly and take up almost no space.