I’ve been meaning to post about this for a loooong time, but I never seemed to be able to get around to it.
I was sweeping up my bunny’s poops one day (he doesn’t really use his litter box, sigh) and I saw a poop that looked rather strange. It looked like a double poop, but less bumpy, more of a smooth oval cecotrope. Bunbun came along and ate half of it. HALF! I picked up the other half and peeled it apart (heh sorry kind of gross). The other half was a ball of fur!!!!!! I peeled apart some other poops, and I found around two or three more fluff ball poops, except they didn’t look like a cecotrope, it looked like a regular poop ball.
It was basically regular looking poops, but when you peeled them apart, a tightly rolled up ball of rabbit fur would show up instead of sawdust-like hay and pellet pieces. I’ve never seen them again, but I’m still wondering – what was it??????????? I couldn’t find anything else like it on the internet! 
Sorry it’s so long…