Flickr's "New photos from friends" e-mail
I don't know how new the feature is; however, I recently started using Flickr's e-mail update feature that sends an e-mail digest of all of the photos your contacts have uploaded in the past 24 hours. It makes keeping up with Flickr so much easier for me.

Sure, RSS is cool and I check Google Reader multiple times per day; however, I am constantly checking my e-mail. So the ability to get an alert with thumbnails in my Inbox is awesome.

I'm glad to see Flickr recognize that e-mail isn't dead. I'd like to see more "Web 2.0" companies embracing e-mail as well as RSS.