How many sex positions are there?

I was having a discussion with a friend a while back when she claimed there are 69
positions. I felt that in fact there are only 68, and bet her £50, on condition that she
prove it.
She accepted my bet, and we arranged to set aside the next weekend to settle the
matter.
We warmed up in a 69, my favourite number, and then got down to serious business. We
did it doggy style, we did it several ways in a chair, we did it standing up.
We spooned, we did it in full and half lotus, and we did the wheelbarrow. We had sex in
ways I can't remember, and often we would return to 69 to re-lubricate. Late Sunday
evening we had tried 66 positions, and my friend could not think of any more. She asked
me if I could think of any we'd missed, and being a gentleman
I replied, "Well, there's head to toe."
She lay on the bed, legs slightly apart, and I got on top, taking a big toe in my mouth to
add to her pleasure. Suddenly she remembered the airplane position, and told me to spin
slowly like a propeller, maintaining penetration all the while. This eventually brought us
into... the missionary position. Best fifty quid I ever lost.