Although I appreciate the exuberance at the choice of Wasilla's finest to join the McCain ticket, why are people donating money to the McCain campaign in response? It's dead money - although it does remain to be seen how long McCain's crack internets team keeps the contribute page up past its sell-by date.

From the letter-writer quoted in the link:

I suspect the money race will be neutralized at worst, and quite possibly turned in our direction. I’ve been sitting on my wallet since 2004, but sent in a contribution to McCain the moment I heard of this pick. I suspect I am far from alone.

Yes, but you're also far from smart. As of next Friday, McCain's stuck to $84 million no matter what. There is a subtle poetry to the abject uselessness of the gesture, though.