I have taken the liberty of writing some suggested Terms of Service for new sites that use Twitter as their basis. Existing sites can also steal this if they like. I won’t even ask for credit.
“By signing up to this service you agree to give us one of the single most important pieces of information about your Twitter account – your password. You acknowledge that this gives us complete control over your account.
You agree that by using this service we may use your account to spam our shit. And we will. Oh boy will we ever. If we do a decent job about it, it’ll look just like something you wrote and people won’t know its us spamming our shit until they see a whole flood of identical messages clogging their stream.
You agree that you’ll probably use this once and then forget about it, like so many others before. Its ok, we won’t feel too bad. After all we both know what this is, a fleeting moment of curiosity. We’ll still have your password though.”
Seriously people, get with the OAuth.