The Lenovo Business Laptops always were super strong for me.
A bit on the heavy side (at least on the older models), but build like a tank and has an awesome keyboard.
But any halfway decent Laptop will run Linux fine.
Some/Many robot vacuums can be flashed with custom firmware and then only communicate locally.
Unfortunately it seems the software isnt as polished or well as cleaning, but i guess some less efficient cleaning vs phone-home crap is a good counter.