From Mashable:

Buying someone a drink in person is a nice gesture, but buying someone a drink via Twitter is, well, not something you do often.

Online networking app Tweet-A-Beer hopes to change that and make paying for other Twitter users’ drinks more of a habit. The web tool officially rolls out at South by Southwest.

Here’s how it works (flip through the gallery below for a visual tour): Tweet-A-Beer uses Chirpify — an ecommerce platform that lets you buy, sell and donate money — to sync your Twitter account to your PayPal account. You can safely send beer money in $5 allotments.

Go read the rest, so that you can safely send beer money to ne’er-do-wells like Iowahawk, who might squander it on stuff like cars.