These are all Snape/Lupin-centric projects written by two or more fans in collaboration.

Lupin_Snape Community Projects:

Chocolate & Asphodel - the first Snape/Lupin fanzine with stories and art created specifically for the zine by various writers and artists from lupin_snape. Downloadable in pdf format.

The Lupin/Snape Fan Art Mood Theme - created by various members of the lupin_snape community. Downloadable.

The Snupin Calendar - an 18 month calendar with art and drabbles by various artists and writers from lupin_snape for each month. Downloadable.

The 2009 Snupin Desktop Calendar - a fan art calendar to use as desktop wallpaper on your computer.

Other Collaborations:

Blessed Moon - community housing collaborations by Arionrhod and McKay.

The First Fall - a post First War serial story written by Hiddenfantasy and Severity_softly.

Hate Love Letters - a Snape/Lupin project along the lines of Shoebox Project. It hasn't been updated since October, 2004.

Placet - an archive of fics and plans set in the Placet universe, an intersection of Dorothy L. Sayers's Wimsey and Parker families with the staff, students, and alumni of Hogwarts. Written by mechaieh and Catrinella.

Ruat Coelum - an archive of the Snape/Lupin storyline from the Ruat Coelum RPG.

Time of Storms - a community hosting an on-going post-HBP serial story written by Arionrhod and McKay and illustrated by Karasu Hime.

Vicious Moon - a Marauders era (set in 1979) serial story written by Innerslytherin and Thesnapelyone.