I didn't come up with this, I got the idea from https://www.matterhackers.com/articles/retraction-just-say-no-to-oozing when I couldn't not seem to get the file they were providing. Someone later posted a file in the comments http://www.thingiverse.com/thing:1240361

I created it in Fusion360

I use this to see if I am getting any stringing or print issues in general. There are tons of test prints out there, my filaments have to be able to print this cleanly before I move on to anything useful.