Here is a short (for me) crossover between two of my favourite verses...
Title: In the Garden
Summary: In a garden, especially a magical dream construct of one, you never know who might come walking down the path.
A Supernatural/Doctrine of Labyrinths crossover. This takes place pre-series Supernatural so no changes to canon there, but it's mid-Corambis (the final book) for Doctrine of Labyrinths so it's mildly AU for that series.
Characters: Felix Harrowgate, Wizard (formerly of the Curia); Thamuris, Celebrant Celestial (of the Euryganeic Covenant); and Dean Winchester, Hunter (and general badass)
Disclaimer: I don't own the characters, but I did have fun playing with them. I give them back essentially the same as I found them.
Rating: PG / Gen
Contains: Language, magic, magical bees, no violence, but there are mentions of past rape/abuse/torture (canon), serious illness of a major character (canon), and essentially no plot.
(So if you find it somewhere else, please let me know.)
In case anyone isn't familiar with the fandoms I played in...
Supernatural is a TV series about 2 brothers who were raised from a young age to fight monsters and supernatural beings. I love the hell out of the first 5 seasons. What a story! (They lived out of a Chevy Impala for the first half of the series.) http://supernatural.wikia.com/wiki/Supernatural_Wiki
Doctrine of Labyrinths is a 4-book series written by Sarah Monette, whose awesomeness I cannot adequately describe. The world-building alone must have taken her years, and yet there's no emphasis on it. In fact, her characters take it mostly for granted, because, of course, they live in it. Warning, these are not “light” fantasy in any way. http://tvtropes.org/pmwiki/pmwiki.php/Literature/DoctrineOfLabyrinths