If I had 50m untaxed... the list can go on forever but here's some stuff I'd do:
Invest at least 15 mill, possibly 20
Leave 10m in some savings accounts and don't touch it
Warehouse full of exotics in my back yard. My house would be surrounded by 12 foot walls, accompanied by 1-2 security guards outside of the gates to my property. I'd always carry a gun with me just because. Would also need houses in different places so I can travel without having to rent a hotel, places such as Tokyo, London, California, Rome, Athens etc...
Have judges/cops on pay roll, waltz around MTL like I own it
Learn how to fly a helicopter and/or jet, buy one for each house that I own incase I need to get somewhere fast. first class is for chumps.
A bunch of expensive suits and clothes, also includes watches, shoes, sunglasses etc. etc.
Build a super gaming computer with the most expensive graphics cards possible. I would use it for my personal recording studio.
Every NES/SNES/N64 game ever created. I'd have an outrageous game collection and a home theater in the basement.
Roland V-Drums TD-30KV V-Pro Set
Learn a new language or two, have a teacher come to my place for private tutoring
Spend 20k on a mountain bike for the lulz (Focus Raven 4.0)
Help out friends/family (especially my parents) and make everyones life alot better
Hand pick a few homeless people, get to know them a bit and why they're homeless in the first place, and then hook them up with 2 years rent paid in a nice apartment with $5,000 gift certificate to Adonis for all the food they need for months
A couple pounds of Kush to share with people I like, and to smoke myself throughout the year. Would also buy exotic wines and cognacs for special occasions.
Donate a few hundred g's to some charities of my choice, but I'd make sure they're legitimate and for a cause I actually care about
A shit load of organic foods and supplements for the gym, along with my own personal chefs that chill at my house to cook me food whenever the fuck I want
Go to some auctions, and buy some artsy shit to decorate my home with. Maybe buy a Van Gogh or something.
Go to a bunch of restaurants and fast food joints, see how people work and how the customer service is. Give a 10,000 dollar tips to people living pay check to pay check with a shitty life, especially if they have kids and rent to pay
Never pick up bitches who are eye balling my car and I, because I'd rather have my cat or dog chilling next to me in my 2 seater Lambo. I'd literally drive around in an Aventador with the top down and my dog would be chilling in the passengers seat with some Armani sunglasses on, looking all superior and graceful as shit
Fly a few people to my place for a mansion party, actors or people whos music I enjoy for example. I'd also have Koji Kondo (guy who created soundtracks for games such as mario 64, zelda 64...) come over to play some videogame theme songs on my grand piano while I eat a steak and lobster dinner
Pick 10 people on MR and give each one of them a car of their choice, under 100k. I know how it is to want a car so bad but you're stuck saving and you won't have it any time soon..
I'd also mess with people who really deserve it by contacting their boss, and paying off their boss to fire them. Would also do immature pranks on a larger scale across Montreal and other cities out of boredom.
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I'll end the list now before I get carried away because there's just too much you can do. I'd give away alot of stuff and help alot of people, but that's ok because with that type of money I can sit on my investments and make money off of interest without even lifting a finger. I'd be making money as I take my morning shit.
Money = freedom = happiness. Period.