youtipit.org is a great Flattr-like service, except that it uses bitcoins. You can still provision your account using Paypal, but it will be converted into bitcoins and you'll be "tippiing" people with bitcoins. And of course, when someone tips you, you'll get bitcoins, instantly. You can choose to "tip" someone else with them, or withdraw them to your regular bitcoin wallet. I think this service is really a great news.