I've found that when filament is really squished into my textured bed, a brass brush really isn't enough to get it out. Sticking filament to it and pulling it off DOES work though. So this creates a grid that can be used to clean off stubborn filament very thoroughly. You can change the line density, the size of the area to clean, the size of wall, and the layer height. Note that setting the density higher than 10% can make it render extremely slowly.

Included some default files that have a 10% density, 0.2 mm walls, and 0.2 mm layers.

Can also be used as a very thorough leveling test if you're so inclined.