"Think before printing."
Since I've been working at Staples Copy & Print Center, I've witnessed more environmental atrocities than I ever thought possible. It's not my place as a "sales associate" to tell people not to print things, but there are limits. My quick list of things that should never be printed: Powerpoint Presentations (They're meant to be presented, not read! If you're printing a hundred copies for your audience, they're going to ignore you as you present, then either throw away the handouts or file/forget about them.), EBooks (They're called "EBooks" for a reason, folks! Read 'em online!), anything Copyrighted (Because it's usually against the law to do so.), and Wikipedia Articles (Again, they're online, and not going anywhere anytime soon, so trust they'll be there, or save a version of the page on your desktop...but keep in mind, that wikis are designed to change so check back regularly.).
I don't want this to turn into a rant, (which may happen because I just spent about $80 on printer cartridges) but instead, just ask that you think before printing that huge document. Ask yourself "Why" you need it printed as opposed to on the computer. Think about what your audience will do with the printed material after you give it to them. Test your ability to do without or work with less, maybe printing one desk reference guide instead of enough for your entire office, for example. You just may save yourself some cash, some trash, and some hassle of empty ink cartridges.