I've never quite been into the whole public thing, but I think that a lot of my readers here at My Gay Sites are, so it would be wholly inappropriate for me not to at least mention a few places where you can go to see boys around and about doing their thing.
So what's on the menu today? Check out /r/PublicBoys for me - a place where you're going to see horny, hung studs that are in public locations and getting down to sucking cock or taking it in the ass. What you'll see are hiking snaps, pictures of dudes by the beach and club sex in Spain. It's a pretty wild ride and so long as it's in public and involves guys, this place is specifically designed for exactly that.
Anyway, /r/PublicBoys currently has 9,000 subscribers and is pretty much 100% gay material. It's owned by /u/GayGiles and he seems like a decent dude, so yeah - two thumbs up!