I bought a New 3DS a month ago, and it is awesome. With the Stable 3D, I just leave the 3D on all the time. It's amazing, and gives a new element to all my old games. Everything loads a lot faster, too. It's especially noticeable with Smash Bros.
Recently, Nintendo released a Free-to-Play game called Badge Arcade. It's claw machine games where you catch badges to stick on your home screen. It's $1.29 +tax for 5 plays. Otherwise, if you're a cheap-ass like me, you'll just take the free plays they'll give you every-so-often. Also, there's a practice game you can play each day. Every 10 practice badges you collect will get you 1 free play.
I've been playing it for the past couple weeks, and I'm up to 86 badges. I haven't spent anything, yet. I highly recommend giving it a go.