What to do with a gazillion dollars, wherever it might come from:
Pay off mortgage, finish renovations, build a nice new garage.
Buy myself a whole bunch of musical instruments: For starters, I'd get a double French horn, an alto sax, an electronic drum kit, a nice flute, several guitars including a '59 Les Paul and a Rickenbacker 12-string, a cello, a viola, and a real (non-electronic) piano.
Music lessons (particularly for French horn, which I've never played...)
Tuition: For myself, a B.Sc. (and probably a language course or two on the side); for my partner, a B.A. in English; and whatever my daughter wants to study.
Trip to Iceland, Norway, Germany, and the British Isles.
BMW 325is.
A motorcycle.
And donations to no-kill animal shelters, safe houses for victims of abuse, the local food bank, and a
lot of websites.