For the last year or so, it has been hit or miss trying to buy denatured alcohol at Home Depot in my area (DC/Virginia). Home Depot is well stocked with every other kind of solvent -- xylene, acetone, lacquer thinner, turpentine, mineral spirits, whatever. But no denatured alcohol. When you can find it there, the price has risen to about $12 per gallon, up from about $8 or $9 per gallon two years ago.
Denatured alcohol is primarily ethanol, with some methanol added so that people won't drink it. I put it in a plastic spray bottle and use it to wash down brake dust when I'm working on brakes. It is cheaper than store bought brake cleaner, and far less toxic. And it evaporates fast. Denatured alcohol is a fairly gentle solvent which is generally safe on plastics, unlike acetone. Mineral spirits leaves an oily film, and is not always kind to rubber seals. Of course one should never use mineral spirits on brakes.
I wonder if there is a real shortage of denatured alcohol, or if this is Home Depot having a problem with its supplier?