I also started Thinpaking all of my anime and movie DVDs a few years ago when shelf space became a huge issue. The end result is that, $70 or so later, I have pretty much quadrupled the room available for my media. It's a pricey option (I always go through Tapesandmedia.com since their Ground Shipping is, literally, cheap Next-Day Delivery since they ship from across the LI Sound) but it's WELL worth it.
Here's how I mostly approach my media:
Single Clear Thinpaks:
Used on movies I love/will keep. If I want to get rid of it, I'll sell it to a friend or a CAGer with the Thinpak included. I use a simple photocutter to easily take off a little bit off the DVD cover so it'll fit easily in the cases. It's a significant amount of cover, to be fair, but it rarely cuts into the graphics or the text on the back. Quick, simple, two packs fit where a single DVD case would before.
Double Clear Thinpaks:
I use these on series of anime or whatnot that I have. I use one cover for the outside and I toss the other cover on the inside as well. It gets a bit cramped and a little bit harder to close but it still shuts completely and does its job. Toss both discs in there and I end up saving about 1 1/3 DVD cases per every 2 DVD cases I go through. It has REALLY slimmed down my collection and, even better, some covers only take a very minor trim to fit into the case without a problem.
Considering how well this has been going, I'm even considering taking it to my games. Yes, I know, blasphemy, but I've sold/gave away/got rid of most of the games I absolutely couldn't stand. Everything else that remains are titles I would mind slimming down a bit just to save room. Considering there's no room left on my wall I've got to take drastic actions sooner or later.
[Edit:]
I use binders for gaming as well, primarily at school when I want to bring a lot of games but want to use only a little space. Theft and condition issues are heightened, of course, but there are easy ways around that. It's nice to have everything at hand and yet only take up a minimal amount of room but sometimes you just don't have any additional space for the old jewel cases/DVD cases, manuals, and whatnot.
If you REALLY want to use the least amount of space possible I'd say go with the binders. You tend to get the most bang for your overall buck. But if you want to have something that takes a bit more room (but not too much) and ends up being mostly accessible I suggest the Thinpaks. Easy storage, very reliable, quite inexpensive in bulk.