Maybe other blades are good, but nothing beats X-acto. These chisel blades are great for a number of things, but I use them mainly to clean dried glue and paint off hard surfaces. In one careful swipe, it complete separates the substance from the surface, leaving it smooth as glass. By the way, if you buy the whole set of X-acto blades and knives (at a very reasonable price!), they come in a beautiful hardwood hinged box.
$2.79 
Nothing beats X-acto