Something I really like is having sex in naughty places. Don't get me wrong bed is great - you can relax and do just about anything, but every now and then fucking somewhere you shouldn't is such a turn on.
I remember making love at the beach, in the water. The weightlessness made it all so effortless and knowing other people could see us from a distance was such a turn on. Sure they couldn't see anything much (though if they stared they would have known what was going on!) but the idea of it *groan*.
Maybe we'll go to the pools this afternoon....