Also, I have spent far too long playing it. And approximately the same amount of time making a case for it. Knitted, of course. Pattern also under cut.
If anyone wants the pattern (as created by yours truly) comment here and I'll spend some time writing it up.
A pink version without the handles - used plastic hoops and pink ribbon as ties instead.
Edit: The Pattern!
Copyright Tanya Fish, not to be used for commercial purposes, and all that.
I used normal acrylic double knitting wool. Size 3.25mm needles (bamboo, but it doesn't make a difference). You need a darning needle to stitch it up at the end.
Cast on 28 stitches.
Row 1: K2, P2 - repeat until end.
Row 2: P2, K2 - repeat until end.
Row 3: K2, P2 - repeat until end.
Row 4: K2, P2 - repeat until end.
Row 5: P2, K2 - repeat until end.
Row 6: K2, P2 - repeat until end.
It should make little squares. Continue until you have done 90 rows in total.
Cast off the first 8 stitches. Put the next 4 onto a stitch holder. Cast off a further 12 stitches. Put the next 4 stitches onto a stitch holder. Cast off the final 8 stitches.
Take either of the four from the holder.
Repeat until the strap is 44 rows long.
Do the same for the other 4 stitches that you saved. Tie off any loose ends and weave in the spare bits.
Then, fold the case 33 rows from the non-strap end. Sew up the sides, leaving the loose flap with the straps on.
Sew a button to the top (case end) of each strap.
Poke a pencil or similar into the end of your straps to loosen up the stitches. Jiggle it around a bit, then you should find that you have a buttonhole the lazy way. Wrap the straps all the way around the DS case, and fasten onto the buttons.
Any questions, comment or email. :) In addition, if you make this please email me a picture, it'd be nice!