Here is a link to the playbooks for a Mass Effect hack I've run at a few conventions. I also have some material for running the game that I will try to post soon.
https://docs.google.com/open?id=0BzUTkdniNXM1MHVFVVNKVEp4bFE The basic pitch for the game is below. It's set after Mass Effect 3. If you know the game, you will see that I made some assumptions about what choices were made during the trilogy. The assumptions make it easier to explain why the player characters are Spectres and are all together on one ship. Also, playing after the trilogy means there are fewer constraints about what can happen and less of a need for people to know the details of galactic history. This has been a boon for players who like science fiction, but for some unfathomable reason have not played Mass Effect.
"The Reaper War seems unreal now: cities burning, society in chaos, families set to panicked flight, the Citadel turning from the hub of galactic civilization to a corpse processing factory to a super-weapon that won the war. The legendary Commander Shepard united the galaxy like never before to destroy the Reapers. But, because the mass relays were badly damaged, the galaxy quickly fractured into isolated regions. Devastated by war and cut off from support, each system struggled for survival. From disintegrating families to the collapsing interstellar corporations, war has impacted every aspect of society. Two years later, the Council has repaired the mass relays and is determined to re-build what was lost. You are a newly appointed Spectre, a member of the Council’s Special Tactics and Reconnaissance branch, with extraordinary legal authority to restore galactic stability at any cost."