Here is my rip off of rkellog's mount... Works GREAT except my phone shuts the screen off when it detects a magnetic field (for flip cases and the like).. So eventually I'll have to root it to fix that. As it is, if I wiggle it around a bit, it works fine.
I also tried putting a wireless charger in there. It fit fine, but the phone had to be placed super precisely for it to work and I wasn't happy with it... I might try again in the future.
Thanks for the idea!
I had to do two sets of magnets and metal plates to hold it... I couldn't put them in the middle because I use wireless charging at home and the plate would block it. One big magnet and plate like rkellog did would be much easier.