The only script I know of off the top of my head is from
http://domainportfolio.us
It's geared towards listing prices for selling your domains., but it lets you list the expiration date and what registrar the domain is with, and you can always put it on an internal-only website.
I'm pretty sure I have some more scripts bookmarked, I'll have to reply later when I get home and can check my bookmarks.