Summergen
The Supernatural Gen Fanworks Exchange, widely known as Summergen, is the oldest ongoing exchange in Supernatural fandom as of 2018, and the second-oldest Supernatural fanfic challenge after SPN_J2_Big_Bang: they both first ran in 2007 and are the only challenges from that year still running, with SPN-J2-XMAS as the only still-going challenge to start in 2008.
Summergen is for gen fanworks only: platonic and non-sexual. It is timed to entertain everyone during the summer hiatus when new episodes of the show aren't airing. Participants sign up to write at least a one thousand word fic or equivalent amount of art for another participant in exchange for someone creating a work based on their prompts. Then the fics are anonymously submitted to the community and posted by the mods. Finally, after all fics have been posted, a masterlist reveals who wrote each fic, and everyone is free to crosspost wherever else they like.
- 2007: 59 fanworks
- 2008: 68 fanworks
- 2009: 87 fanworks
- 2010: 73 fanworks
- 2011: 52 fanworks
- 2012: 75 fanworks
- 2013: 69 fanworks
- 2014: 88 fanworks
- 2015: 74 fanworks
- 2016: 72 fanworks
- 2017: 58 fanworks
- 2018: 70 fanworks
Many Summergen works can be found in the AO3 collection, but for the full lists of works check out the tag on LJ!