Got this comical shot yesterday. I heard them shuffling around on the floor and was surprised to see them mating near the kitchen - they have rarely ever mated on the floor and I haven't seen them do that for several years. When I got closer I discovered why.
Normally the female will squeeze out from under the male if he tries to mount her on the floor, then makes a hasty retreat to the rug and waits for him there. It seems she was checking out one of my thongs (flip-flops to the Americans among you) and was in the process of crawling through the strap when the male approached. I'm guessing the friction of the thong on the floor prevented her from being able to squeeze out from under him. The other thong can be seen behind them.