Fair outcome using unfair coin I have been thinking a lot about the following puzzle, but could not arrive at a solution.

Can someone explain to me how can you get a fair (equal probability) outcome using only an unfair coin (where unfair means that it will land head with probability p and tails 1-p where p != .5)?
It will require some extra tosses, but you can get a fair result this way:

Always use two throws to determine the answer, a HH or TT throw is discarded.

HT == True
TH == False

You know that the probability of HT is the same as the probability of TH.