The only reason Joseph does not remove paper from the printer is:
a.) he does not see the printer; or
b.) I have not replaced the paper back since he last removed it.
While making a phone call this morning, Joseph happily entertained himself near the printer. After I put him down for a nap, I found the following in the trays and crevices of the printer:

I have this dream that one day I'm going to get a printer with a hidden paper tray. Aesthetically, I think printers look better with the paper hidden, but now I have even more motivation to get one.
At some point a couple months back, I forgot to recover one of our electrical outlets with our plastic safety covers. The next morning, I stumbled across the following scene:

Joseph also loves to "fix it!"--which is his name for picking up my tools and getting into mischief.

Ever since he's been mobile, Joseph has enjoyed being my helper. We've assembled (or re-assembled since we moved) a lot of things together including: his crib, garage storage shelves, bar stools, a china hutch, closet shelves, curtain rods, and the porch swing.
Building stuff together usually takes a lot longer--especially since he still really doesn't like the sound of a power drill, so I have to use it on the sly--and I never quite know where the hex keys will end up, but I think we both enjoy our bonding time.
I also have the advantage of knowing that everything is sturdy and secure, because my helper stands on each part as it's being unwrapped or put together.