Right now, I have them on a bookshelf. Holes are cut in the back to allow for charging cables to go through:

As you see, I'm running out of room. I suppose a solution for this could be to buy another bookcase to put next to it and stack the portable game bookcase on top (and I'll have room for this when I move in three months), but I'm just curious to see how other people do it.
How do you guys display your portables?