Adapted from the original thing for printing in one piece, as well as some other changes to make it actually tip when printed in one piece (oblate sphere). Two halves on one plate or the entire thing. As bonus, same for original. Sanding needed!

Note that this is actually the tippe top according to the 1951 German patent. First patent of 1891 does not have a cylindrical cut-out.

ProTip: print one at 10% infill and 1 extra boundary layer (=normal top ) and one at 95% (=tippe top). Give the one of 10 to a friend, and tell him to make it tip like you do yours :-)

[update 10 dec 2012]
You need to follow parts of these instructions to obtain a working tippe top.

Other tipping tops: thing http://www.thingiverse.com/thing:38459 and http://www.thingiverse.com/thing:45822

1/ The tippe top needs a correct weight distribution to work. Printing at 95 to 100% infill should do the trick. I print at 95% to correct for unaccurate feed thickness and it works great

2/ The tippe top tips due to the friction force. It is hence important that the surface is sufficiently smooth to allow for tipping. I use sand paper 100 to remove unevenness. If there is a ridge on the surface due to the print, remove it with a dremel tool. If the tippe top is "jumping" from bubble to bubble, there will not be enough friction to tip.

For the same reason, the layer thickness should be low. Like this rolling and slipping is more guaranteed. I used layer thickness 0.18 mm on my replicator.

3/ Try to print in one version. For this, use external support. You can print with the peg down or the head down, both will work after removing the support and sanding the surface. Note, if you print with head down, the heat on the peg might distort it while printing it.

4/ there are different files here. The scad has options to produce all of them. Original is a form close to the original, thing http://www.thingiverse.com/thing:10291
Nopeg and peg should both work, single plate and full versions given.
On trials, I cannot determine which one is actually better :-)

5/ The LARGE version is like the normal version, but with a shorter stem as jumping on a high stem is impossible for a heavy top. You can scale the LARGE version normally to whatever size you want. The large version is harder to spin, and uses a lot of plastic. However, you won't be able to buy such a large tippe top :-)