This is a set of brushes I've created for inking in Inkscape and Illustrator. I've released them in SVG format in order to make them usable in multiple vector drawing programs and enable artists to incorporate them into their own custom brush sets. I made the square brushes 4x4 points, giving some a zero-opacity strip to make them square. I designed the longer brushes to use as "feet". They range from 5 to 17 points long. The images below explain their usage in Illustrator:
I personally don't use even a quarter of these brushes most of the time, but I made as many as I could think of in case others find them useful. I expect to update this set frequently as I design more brushes and try to think of names for the existing ones (suggestions welcome!).