There are others but http://completionist.me/ http://completionist.me/ works the best for me. Shows the averages and also has things like "this many games are u

There are others but http://completionist.me/ http://completionist.me/ works the best for me. Shows the averages and also has things like "this many games are under 5 percent completion" so I can go find something I booted up once and forgot about. I also use steams category system to then tag some of those into a backlog category, although that doesn't help as much