Off-Canon is the term used for "for fun" side-stories written outside the main roleplays. Both SegaStH and SatAMStH have a respective forum dedicated to these. Most often they're made for the sake of being lighthearted and silly, but some are also made to be and taken seriously.
Off-canons are mostly used to explore possibilities, situations or play games that are otherwise unlikely or impossible in the main roleplay's canon. They may range from completely outrageous situations with characters possibly acting entirely contrary to their normal portrayal, or ideas such as alternate dimensions and travels through time. Not all off-canons are in a novel format, some are actually created as add-on comics.
While most off-canon threads are made on a whim and and may die off quickly, some are continuously on-going.
Noteworthy Off-Canons
The Water Cooler
Inside the Sol Dimension
SegaStH Comic Jam
The Great Player Shuffle
Westopolis Idol
Sega/SatAMStH Crossover
Technically more of an 'alternate-canon' than an actual off-canon, the Crossover is particularly noteworthy. Instead of an individual thread, it's treated as a whole roleplay unto itself. It contains its own specific playing field, OOC talk and archive forums on both boards, is continuously on-going and has gradually begun to develop its own continuity. For further information, please see its main article.