Magnetic Photo Hanging

I have tons of super strong magnets left over from my Magnetic Cups project (see here and here because my website is down :( ). A few weeks ago I devised this photo hanging system: binder clips on the top and bottom of each photo, with magnets linking them all together. The top magnets are stuck to the wall with foam tape, so no holes in the rental walls. And it's easy to swap out photos or add more to the collection. The magnets are so strong that you could hang photos like this from ceiling-to-floor. Sometimes I worry that I will get so out of control with these neodymium magnets that someone with a pacemaker will not be able to step foot into the house...