The Six in One Painters Tool
I always seem to get strange looks for carrying this tool, as I am not usually painting, yet I find myself using it for so many things that I wonder why everyone doesn't carry one. I use it as a putty knife, a scraper, a light pry bar (works great for lifting trim), it can lift small nails, turn screws, even philips, with the small pointy end, and can even be used as a light chisel.You could even use it to open paint cans and clean rollers.
They only cost about ten bucks, so it is not a real big deal if it breaks or wears out due to use or abuse.