Link for the impatient: http://kkmet.com/random-lol-skin/
From the creator of the ping visualizer (this one if you haven't seen it: http://kkmet.com/ping/)
I saw the request for "select random skin" feature numerous times, I wanted that too, so I made it myself.
you can exclude specific skins, and they will be saved until the next time you visit (so you don't have to exclude the skins you don't own every time you use it)
ad free and always will be (I don't need the money, but your gratitude makes me happy)
This took about 5 hours to make, if you thought of any improvement please share it, if it got enough attention I can pour a few more hours into this.