1.The Tickle Quiz.
Better if your victim is more intelligent than average. Tell him if he can answer the next question, you'll untie him and let him go.
Me: What's the capital of North Dakota?
Me: Sorry, wrong answer.
Proceed to tickle him for five minutes despite his laughing protests and shouts of "unfair!". After the five minutes are up, realize he was right, look sincerely apologetic, and say you'll take the punishment back. Tickle him for five more minutes, except in reverse.
2.The Rib Count.
Yes, it's an old one but a really good one. Nevertheless, time to toss it out and get something new. Best if you tie him on his back and stuff pillows just below the shoulder blades. This makes his ribcage protrude like nobody's business, bringing each and every single rib into delicious focus. Claim your sister told you once that men have one less rib than women because God took one out when he made Eve. Say you want to take this opportunity to do a scientific test and afterwards you'll untie him and let him go. Proceed to count slowly from the most terribly sensitive bottom ribs, taking exquisite care to press down into each rib with your fingernails, as well as the exploring the full length of the gap between each rib. Make a production out of saying "One!" then proceed to the next rib. At the fourth rib, say "Five" instead. Stop and look puzzled. Claim his laughing distracted you so much you lost count. Tell him not laugh this time and begin again at one. Repeat at least ten times.
We all know this one. At some point during the torture he may shout out the words "Don't!" and "Stop!" somewhere in close proximity to one another. Say "Don't stop? Well, I was just about to stop and let you go, but if you insist ...". Renew the torture. This has the advantage of extending the session at least five more minutes while appearing to have true concern for the wants and needs of the victim. But really, it's become such a tickle cliche and you can only really use it once per session. It's outta here!
4.The Clock of Death.
Give your victim the choice of being tickled for one hour, but at very short intervals and with plenty of time to rest between, or being tickled straight and nonstop for five minutes. He will always choose the five minute option so as to get it over with quickly. Bring out The Clock of Death where it can be plainly seen and set it for five minutes. Begin vigorous and merciless tickling. At 30 seconds before the five minutes are up, the second hand begins to move backwards. Victim will scream but you can continue tickling for as long as desired. I actually made this clock in my high school shop class (I began using my powers for evil at a very young age).
5.Let's Make a Deal.
Tell him he has a choice of where he will be tickled next before you let him go. He must choose 2 of the following 6 areas of his body: feet, knees, sides, bellybutton, ribs, armpits. After he has chosen his two, proceed to ignore those and tickle the other four vigorously. Deal must be delivered solemnly and with an absolutely straight face. Better if victim is not too bright.
I found this one to be a lot of fun during tickle wrestling, i.e. not during a full-fledged bondage ordeal. When he is pinned and firmly in your control, offer to make him a deal. Tell him you want to see if he really trusts you and to prove it, he should raise his arms over his head and firmly clasp his fingers behind his head. He will balk. Swear ON YOUR MOTHER'S GRAVE, cross your fingers, hope to die, and offer to jab all sorts of horrible sharp things into your body if you are lying, that you will NOT tickle him. Bring your index fingers slowly closer and closer to his underarms. Press them lightly into the hairy part, pause, and proceed to tickle his underarms to death for as long as you can get away with it. Apologize afterward for being such a pathological liar and swear on your mother's grave you thought he knew that. It's painful to toss these out, I know, but I'm sure I'll get some great suggestions from the rest of you.