An overlooked category that is very Hugo-rulesish. The rules basically are that it has to be published periodical, have at least four issues in a year, pays its contributors *OR* is sold for actual money *BUT* doesn’t actually make money for somebody. In others it is more like a professional magazine than a fanzine but is still primarily a labor of love.
In terms of pop-culture/SF websites something like io9 or The Mary Sue don’t count because they are published by commercial entities, whereas Black Gate does because, well because it does [ETA: or maybe not – consensus is that it is a fanzine nor a semiprozine]. Of course this makes it a very insiderish category and demonstrates the extra level of abstraction involved in Hugo categories like best fanzine. It isn’t enough to know what SF/F works you like and their relative merits you need to be able to make an informed judgement about the relative merits of magazine/blogs that themselves judge the relative merits of the SF/F works you like *AND* also have some idea of their commercial status.
So inevitably you need a website that provides some sort of guide through and luckily there is this http://semiprozine.org/semiprozine-directory/
I’m going to start working my way through…