The tool I can't live without, for me at least, is electricity. My house is an older house and I only have two outlets in my garage and said two outlets in my garage have shared power with my 3 bedrooms. This being the case, whenever I use my air compressor, I have to make sure that there is nothing plugged in / in use in the bedrooms or else the breaker trips. I would LOVE to have a 220v outlet, more outlets, and dedicated breaker for my garage.
After that, my list of tools would definitely change, LOL.
'97 Bird, "Pearl": L/R 2.5in Magnaflow Hi-Flow CATs | PI Intake & PI Cams | Suspension Rebuild
'13 Taurus, "The Bull": 3.5L Goodness
'00 2dr v6 Accord, "Dirty Girl": Magnaflow Hi-Flow CAT | Greddy SP2 CAT-Back | Eibach ProKit springs | Eibach F/R Sway Bars | KYB-GR2 struts