Universal Inbox/Universal Outbox
FriendFeed was a real-time feed aggregator that consolidated updates from social media and social networking websites, social bookmarking websites, blogs and microblogging updates, as well as any type of RSS/Atom feed. It was created by Bret Taylor, Jim Norris, Paul Buchheit and Sanjeev Singh. https://en.wikipedia.org/wiki/FriendFeed
Here's a nice screenshot of someone's home-page showing updates from multiple users.
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