The Lightning Wallet and Tipping service tippin.me released extensions for Chrome and Firefox that integrate it’s service with Twitter.
You will see a lightning icon below every tweet. By clicking on the icon, you can immediately make a donation to the author of that tweet (on condition that he has a tippin.me account of course).
The plug-in still has some bugs, and doesn’t display in the new Twitter layout, but those things should be fixed soon.
The Chrome extension can be found here:
The Firefox add-on: