I've actually put a decent amount of time into some older games recently:
I'm about 10 hours into a Chrono Trigger replay (since I bought the cart through Zeus). The game goes by quick when you know what you need to do, but it's still fun.
In January, when I had a broken toe and a strained lower back, I put about 15 hours into a FFT replay, but I died a bunch of times at - wait for it - Riovannes Castle and I haven't picked it up since. But man-oh-man is that game still awesome. I caught a contact high from all of the people who were playing the new translation on the PSP, and I'm surprised at how well it's aged.
Two weekends ago I picked up We Love Katamari, which I had played through already, but on an old roommate's copy. I was hankering for some Katamari, and it's still lots of fun.
And I still haven't beaten Twilight Princess, which I started... I can't even remember when. I played a bit over the weekend, and I know I'm near the end, but I'm just doing fetch-quests, and it's not keeping my interest.
Basically, I played FFT because I was injured and couldn't lift or do BJJ. And I put time into Katamari and CT because you can put as little as 15 minutes into them and get something done. Because it takes more commitment to make progress in Twilight Princess, it's been mostly untouched. It's the last new game I bought, and before that, FF12.