Academic

Keep them in a single, clearly marked file.

I consider myself an eminently organized person, but I just got flattered with a request to put two of my older articles into an anthology, and didn't know (a) whether I had the right to give permission, and (b) where the agreements were.  I put law review author agreements right up there with the HIPAA disclosures that I have to sign when I go to the doctor (or maybe the raft of documents during a house closing telling me my mortgage is going to be sold and securitized, then backed by an AIG credit default swap) in terms of "life is too short to bother reading this."  After scrambling around on my hands and knees for about fifteen minutes, I found the first agreement, which clearly provides that I retained the copyright and the right to reproduce.   I can't find the second one, so I have a call into the law review. 

You heard it here first.