I've subscribed to a few of the usual suspects - hitRECord (duh), Joe (really?!), wirrow, sinnamin... but those that I want to explain are: http://www.hitrecord.org/users/bweston23 http://www.hitrecord.org/users/mitebkilled and http://www.hitrecord.org/users/lcd46086
I'm following these three simply because I find their writing thrilling, and don't want to miss new contributions, which I most likely would because this kind of stuff has barely a chance to ever get noticed around here. They are actually fairly random representatives of a depressingly large group.
Also, two honorary mentions somewhere in between invisible and obvious: http://www.hitrecord.org/users/ManWithHat http://www.hitrecord.org/users/cacheth
Simply 'cause I like 'em.