G'day Alex,
Firstly i'd make sure i have no debts
Then i'd buy property (a house,some spare land for an observatory)
Maybe a good sized tinny for my other passion fishing.
Observatory with at least a 1metre scope ,full tracking capability ,some good camera gear for astro work ,Dongas out the back with power to them so you guys and gals could come and visit or stay a while.
Put the rest into some safe investment just to earn a bit of interest.
That about completes my dreams, i think

Cheers