Denatured alcohol is good to have around the shop. I buy it by the gallon and put it in a small dishwashing soap thing (Dawn) and leave it on my workbench. I use it to soak hinges in before gluing them, wiping sharpie pen marks off covering, etc. I also mix it in with my cleaning solution to wipe down my planes at the field.

Other good solvents to keep around (by the gallon)

Mineral Spirits and Lacquer thinner. I buy acetone by the quart because I don't use it as much. Also MEK is good, but is carcinogenic.