Cupid is used to be turned out during the day, so even though I walk him several times a day when he is stalled he gets pretty bored and finds ways to entertain himself.
When we were camping I was happy to see that he was drinking plenty of water - or so I thought. Then I observed him dumping out his water bucket! He grabs the edge with his teeth and shakes it up and down until all the water sloshes out!
Apparently he needed more variety because I also caught him playing with his salt lick.
Even at home he can be a little destructive. The other day I arrived at the barn to this mess in front of his stall. My friend said he looks pretty pleased with himself here!