My Lithops helmuthii seedlings (c271) must have multiplied over the winter. I didn't notice that until I took these pictures, but it's clearly visible that these two came from the same old plant.
I still have them under my energy saving lamp because I thought they weren't big enough yet to be living the "real" Lithops life on my window sill. But I guess it's time they moved into the sun.
This is what they're supposed to look like when they're older: http://www.lithops.info/de/galerie/lithops_c271.html
Lithops helmutii seedlings on May 28, 2012