This isn't an option I particularly want anyone to use, but you can now delete your account via your profile page. It's your data so you get to decide what to do with it, and if you want to leave for whatever reason, we'll try and make it easy.

This will remove all your data from our servers so you'll probably want to download your logs and export your stats before doing that.

Of course, since there is an automatic signup via OpenID, you'll still be able to login, but what you see will be a new empty account.