I'm going to assume that inside the house, you view anything having to do with the kitchen as not practical (at least for you), otherwise I'd put stuff like really good knives, a dough maker/bread machine, a good espresso machine, proper Guinness pint glasses, and an electric ice cream maker on that list.
But if you really want to go "off the board" and had a bunch of friends who wanted to go in on something collectively, I have your answer:
Relax in the Almost Heaven Salem 2-person Barrel Sauna, crafted from premium cedarwood. Order today to transform your wellness routine!
mysaunaworld.com
Sure, you have to build it yourself, but if I can do it, so can you, especially given your apparent tool set. Though you will need to hard wire it to your house. But seriously, it's a no brainer, for health, relaxation, and mischief.