One of the best things about the old school renaissance is its diversity: there are a huge number of folks out there doing all sorts of weird and wonderful stuff in their home campaigns. Precisely because there are so many, it's pretty much impossible to keep track of them all. That's why I'm making it a point today to direct your attention to a handful of people who've done awesome work in either presenting material from their homebrew setting or rules hacks they've made (or both). That they have all taken their games in such different direction is, to me, a feature rather than a bug (to borrow an overused phrase).
A lot of this stuff isn't what I would do, but, then, that's the point. Gaming awesomeness comes in a variety of forms and I want to highlight a few terrific examples of it. In the comments below, feel free to include links to examples of what you think are great presentations of homebrew setting information and/or houserules.
In Places Deep: Evan Elkins uses his blog to present not one but three different campaign settings -- Cuccagna ("The Tempest as written by Jack Vance"), The Dark Country (a Hammer Horror-inspired setting and home to Nightwick Abbey, "the Amityville Horror of megadungeons"), and Uz (a science fantasy in Earth's far future)
Legacy of the Bieth: Humza Kazmi has come up with a setting that combines a vaguely Abbasid/Almoravid era North Africa with the feel of a spaghetti western. If that's not one of the more awesome campaign pitches I've ever heard, I don't know what is.
Mutants and Magic: Paul Schaefer's Gamma Red Death World is set on Earth in the late 19th century after an alien invasion. This is a fairly new setting, so it's still being detailed, but I really like what I've seen so far.
People them with Monsters: Jeremy Deram presents Outland, which he describes as a "semi-gonzo kitchen sink setting." Outland was originally a D&D setting but has since migrated over to Dungeon Crawl Classics Roleplaying Game. You can see Jeremy's house rules on the site, as well as his excellent DCC RPG resources.
Tales of the Grotesque and Dungeonesque: Jack Shear's The World Between Setting is a Gothic fantasy that borrows from literature, folklore, fantasy, and horror. It's one of my favorite homebrew settings these days and strikes me as what Ravenloft could have/should have been.
The Wisdom Frog Croaks: Reynaldo Madrinan presents his Barovania setting, which, as you might guess from its name, is Ravenloft crossed with Japanese video games. It's not quite my cup of tea, but there's no denying that it's quite imaginative. Plus, I suspect my 12 year-old daughter would love it.
Untimately: Brendan Strejcek presents his Pahvelorn setting, as well as heaps of amazing OD&D rules variants and extremely useful resources, such as OD&D equipment post from this past summer.
Wampus Country: Describing Erik Jensen's Wampus Country setting is difficult, but if you were to think "D&D crossed with Oregon Trail," with lots of fairy tale stuff thrown in, you wouldn't be too far off.
I have lots more links like these to share and I will in future posts, but, as I said above, I'd like you to do the same in the comments below. Share links to the awesome old school homebrew settings and rules you've encountered on the web!