I love Swords & Wizardry and I love creating for S&W. It is just the right amount of simplicity and crunch that I want in a game. But I also love what other people have created and still continue to create using S&W.
Personally, one of the greatest things to come out of Swords & Wizardry is Tenkar's Swords & Wizardry Light. It takes the core mechanics and turns it into a four-page folio that has everything you would need to run a game for characters level one to three.
The success and ease of play and modification of Swords & Wizardry Light has spawned other amazing creations. And there is two that I really want to focus on: Light City and Six-Shooters & Wagons.
Light City is a Super Hero hack for Swords & Wizardry Light. It is being created by Jonathan Linneman of Monstrous Matters with the help from Justin Ryan Isaac of Halls of the Nephilim. Unfortunately, there really isn't a complete collected works. The above link has everything that is currently created for Light City. Some of them are just articles while others have links to them on OneBookShelf. But there is one product that I feel is the MUST HAVE if you want to start playing Light City: The Assembly. Just like Swords & Wizardry Light it has all that you would need to start running your first adventures* (I'm sure there is a better word for that) as Super Heroes. It has 3 classes, items and adversaries all on two pages. Also, it mentions that you can use Swords & Wizardry Light with this product (races, classes, items, monsters, etc.) Later, I will eventually make a post and/or file on how to add flavor to Swords & Wizardry Light to make it fit in a game of Light City.
Six-Shooters & Wagons
Six-Shooters & Wagons is a Western, Wild West hack for Swords & Wizardry Continual Light created by Justin Ryan Isaac. For more information I wrote a review that can be found here.
The reason why I am focusing on these products is because I want to see them grow into something larger. I plan on creating some One-Page Adventures designed for these products. Though, they don't follow the typical fantasy structure of adventures. And that is one of the things I want to focus on: A 'how to' create adventures and run these systems kind of thing. When I read through these two products I view the gameplay style/structure completely different from Swords & Wizardry.
*Crises (I believe that would be the better word)