Yep, I found this little gem on the web 2 weeks ago and downloaded the mesh file and got it 3d printed (the material I used was Nylon-PA12) and man alive does it work! Only cost me $7.00 US currency. This little 3d printed lab quality centrifuge when coupled with a good Dremel rotory tool (35000 rpm,) can spin down a sample @ 2136.498 times the force of gravity, enough for a quality DNA extraction.

Here is some pics of the one I got printed and I have already tested it @ full speed with 6 1.5ml sample tubes.

This design is open source and can be found here:

http://www.thingiverse.com/thing:1483

This my Dremel rotory model# and specs:

Dremel model#3000 rpms - 5000 - 35000

Max
G-force @ 35000 rpm
= 2136.498

Shaft Radius = 0.156 cm (this is the shaft I used since the centrifuge center hole was designed to accomodate a standard Dremel shaft accessory.)
Rpm's = 35000