I'm not sure I want to know what Whitey tried last night.
What I do know is that I was busy at my desk when I heard cat claws flailing loudly on steel behind me. The only steel back there is the file cabinet, so I think Spidercat was trying to climb the cabinet so he could visit the stereo and bookshelf.
Or maybe he tried to leap up, and the screech was him clawing as he discovered he wasn't high enough. I do not recall hearing a crash landing, but he is light on his feet. (Billy, bless him, would have left a crater.)
Some things, humans were not meant to know.