Quick Ball, with magnetic clasp

You are going to need to print the blue_1 part with supports. The yellow_top and yellow_bottom piece might also need supports depending on your printer.

Glue the yellow and blue lid and bottom pieces together (you will need 2x blue_1, 2x blue_2, 1x yellow_top, 1x yellow_bottom)

After assembling the lid and the bottom you can glue the button and the ring to the bottom with the hinge in place as you glue the ring down. Then snap the hinge into the lid.

You will also need 2 magnets (1/4" X 1/16"). Just glue them in place.

Netfabb seems to be gone so these files have not been put through a repair program. I've tested the preview from MakerWare Desktop and it seems like the pieces should print correctly but let me know if you have problems.

Tip: Print your bottom piece (dark blue piece) at a higher in fill percentage, around 40-50% and then all the other parts at 5-10%. That way it will be bottom heavy and not roll around as much.