That’s a tough one because I’m currently surrounded by computers and tools. I’m within reach of my smart phone, one of my laptops, I’m typing this on my desktop PC, I’m within reach of three multitools, a power drill, and my away mission tool bag. So I think I’ll give a cop out answer and go with “The several thousand liters of air filling the room.”
Toilets are effective at pushing shit, piss and vomit into the sewer while preventing sewer gases from entering your home, and they also double as chairs when not in excremental use. You can also use a toilet to repair the mental defects of a billionaire if you drop it from high enough, I don’t think toilet paper functions in that way.