I've always thought the same too. I would much rather be dumped somewhere than cremated.
Honestly, I keep telling people that when I die, I wish my body could be dumped into a ditch somewhere, and my skull made into a handy souvenir or something.
In realistic terms though, I'm seriously considering writing my body off as a donation to research or one of those creepy body farms. Later on, though - I don't even have a real will yet, seeing how I don't have anything to will anyone except my student loan papers