i have a couple:
1) The infinite vagina
make both hands into a fist with a hole in the middle. Make sure you lube up your hands, slide one over the head of your penis slowly pushing it down towards the shaft when the head is almost peeping out of your hand put the other one on top therefore creating a tunnel. Then take your first hand and bring it to the top etc.
2) Take your right hand (or left if your lefthanded) stretch your thumb and index apart, there should be a webbing type thing there. Put this just under the head wrap your index and thumb around the shaft and move up and down rapidly the movement should make a vibrating type feeling
enjoy
jack