Grace likes to stick her hand in the toilet. In the spirit of being open-minded about it, I suppose it could look like a fun place to play assuming you have no concept of what lurks in there.
Sometimes she'll play with the plunger or the toilet scrubber and walk around the house, waving it around like a scepter or something. Naturally we are grossed out by this behavior and concerned about Grace's well being, so we try to keep the bathroom doors closed as a result. This strategy will work at least until she is tall enough to open them and by then hopefully she'll have moved on to some other hazardous endeavor.