Chris, luckily the hot weather this Summer killed all my crabgrass so I dont' have to worry about mowing this Fall..
It's kind of funny.. this thread made me realize that I don't have any plain gussets on eBay. Sometimes I get "tunnel vision" and forget to step back to get a better perspective. When I started cutting gussets, all I thought about was "what designs can I cut" with the plasma table. The thought never occured to me to just do a run of plain triangle gussets.. maybe of a few different sizes.
Until I got my plasma table, I used to just cut gussets on the bandsaw. I'd pick up a strip of 1", 1.5", or 2" flat bar, set the saw to 45deg and cut away.. flipping the flat bar over and over as I cut the triangles. You can even shove the bar thru far enough that you leave a little "flat" spot in the corner to fit the "already welded joint". Another trick is to stack 3-4 strips on top of each other and clamp them together with Vice Grips. That way, each cut is making 3-4 gussets at one time.