Also available for purchase via http://etsy.me/13LdXqZ
This is a full periodic table set written in openscad, with magnet holes on the back which will fit these magnets (1/4" X 1/16")
I have exported (i think every) element up to 112 into a zip file for download.
To generate more, you will need to get the fonts package too. The basic function is "element", which takes two strings, the symbol and the atomic number. _alt, _triple_digit, and _triple_digit_alt were added for special formatting needs of some of the elements. Could definitely be more elegant, but there it is.

Print out the elements you want, apply dab of superglue, then insert magnet.
Elements have been exported with their "group name" first, so you can print them in different colors. Bonus points for printing the radioactive elements in glow-in-the-dark (pictured) !