Sounds too complicated. Here is an idea to to prevent click fraud from developing countries. For example if the advertiser bids for $1.00 and sets no retrictions on geographic location of the click. Then a tool must automatically adjust the bid based on the cost of living and currency conversion factor. So a bid for $1.00 for US will become a bid of 1 rupee or so. This will be certainly deter 'The army of Paid Indian Clickers'.

I want to put my Penny's worth in on that last comment
Typical responce from somone in the US, "its to difficult for me but we will penilise anyone else who might want to use it"

This is a typical comment from someone in the USA, That everyone else should suffer by having a "cost of living and currency conversion factor" added on to the clicking process ????

You will find that most of this fraud is not from some distant land its from your own shores since a lot of the PTR start there

Well what happens to the person who wants to pay $1 and the country that they are targeting has a higher cost of living and currency conversion factor than them ???
That would mean that you end up paying more than you wanted to since if it deducts you can be sure of it adding to it

The other thought on it would be that it defeats the purpose of a money exchange since if a dollar is worth £0.50 in the UK. then £0.50 will be worth a dollar in the US so what you are saying is that in somewhere land your dollar is worth £0.10 so who gets keeps the other £0.40 thats missing ?