I originally purchased it to put a desiccated bird corpse in it (I found this sad blue bird in my sisters garage - it had gotten trapped in an old furnace). Unfortunately, the bizarre angle its tail assumed during rigor mortis does not fit.
So now I have to come up with some other ideas.
I could stick some skulls in there like Darling Darlene suggests. Her ideas are fun and cheap. I have plenty of skulls, tombstones, crows, and moss!
These beautiful designs from Rogers Gardens are certainly inspiring.