About a year ago, i took a felting class and decided to make a make-up-bag. At home, it turned out to be the perfect case for my new Nintendo DS! My DS (her name is Bettina, btw.) feels quite comfortable in there!

This is how it works:
Cut out a DS-stencil out of something flat and flexible (eg. foam rubber) but keep sure to make it about 1/3 bigger than your DS, it will shrink while felting.
Cover the stencil all around with wool and felt, felt, felt until its a firm and solid fabric. Rinse and cut it open.
For decoration, i felted small balls in different sizes, cut them in two and glued them on the case.