The Well, one of the oldest still running online communities, has a feature called the bozo filter. The bozo filter lets you block comments from specific people so you would not have to read them in the discussion threads. In a self-contained system such as The Well, this could save a lot of aggravation from having to read the postings of someone you had decided was no longer worth the aggravation. It also helped prevent rehashing the same fights over and over again.
The broader online community, dispersed across innumerable blogs, twitter, FaceBook and other sites, has no universal bozo filter. However, you can control who you choose to follow and read.
Review all the sources of information and commentary that you continue to listen to and read. Are they all still providing value to you? Are any worthy of being bozoed and removed from your subscription and alert lists? It’s healthy communication practice to prune your subscription lists periodically. Otherwise, you’ll end up spending most of your time marking things as read and getting little value from it.