Here's the premise: Sign up, put some cash in your Twitpay account through another payment service like PayPal, and then send out a "tweet" to another Twitpay member, structured like "@josh twitpay $10 for beers." Twitpay takes a five-cent commission. Its founders are hoping that, eventually, it can be used for charity and disaster relief payments.
It's a nifty idea, though not for everyone. You don't get cash out of it, for example--Twitpay reimburses you in the form of Amazon gift rewards instead
twitpay only pays out via amzon reward points rather than cash
