Chrome: With the death of Google Reader, a number of people are jumping ship to popular alternatives such as Feedly, NewsBlur and OldReader. RSS Subscription Extension is an extension that makes adding RSS feeds to those readers a breeze.
RSS Subscription Extension is a fork of the original Google RSS Subscription, but with updated RSS readers. With it installed, you get a small RSS subscription bar in the omnibar to instantly add feeds to the reader of your choice. This extension does the same thing as the original extension, but supports readers that are actually still working. If you've jumped ship to Feedly, Digital Inspiration also has a bookmarklet for Feedly that works in Firefox.