This is a DS Lite Game carry case. Looks simple enough. I had envisioned one to make with elastic strips to slide the games into but I like the clear pouches of this one. Will be making this for my boy for Christmas and I'll probably use a pair of old jeans for the fabric, he outgrows his pants so fast we've got lots of good pairs from which to recycle. The instructions are on Instructables.com
You have to be a member of their site to see the tutorial but it's all free and no spam.