This year, I decided to get serious. I've brought a couple of exercise kettle-bells in to school with the optimistic-to-the-point-of-fantasy goal of using them during my lunch break each day. That clearly hasn't happened, but they DO do an excellent job of actually propping the stupid door open.
Unfortunately, they also leave black marks on the floor that don't come off. So, in an effort to buy some good will with our hard-working maintenance staff, I picked up a doormat to keep the place spiffy.
Doormat - $6.97