They're the equivalent to a hook, except they will hold anything that weighs less than a pound (ish) and has a magnetically attracted metal on it. Your keys, flashlights, pliers, screwdrivers, scissors, and multi-tools all can be held with these bad boys. And since you don't need any tools to create them, and they don't damage walls, these are unbelievably useful for dorms, apartments, and homes alike. Simply put, they are magic.
Step 1: Gather Materials
Not Pictured: You'll also need a wall. And a pair of hands. The pair you're using right now should be fine.
Step 2: Apply Sugru to Wall
Cut open the Sugru packet. All four sides. Now peel the wrapping off. Rub the Sugru around your hands into a ball, just so that you get it warmed up and ready to mold.
The next thing you want to do is press it against the wall wherever you want the magnetic nipple to be. I prefer eye-level, because that way there's no chance my phone could pass by and get messed up by the magnetic field.
Press it onto the wall and put enough force into it so that you flatten it down.