Land, land and land.
Except for books and toys for small yappy type dogs, I can go without most things. I’m not a shoe or purse woman.
Just trees and land not turned into strip malls.
Seriously? How many nail salons need to be within five minutes of driving?
Acres of land, so I’d have room for the cars and animals. Books. Computers and every stupid USB device made on earth–I have no idea why I’m such a sucker for USB trinkets but there it is. By animals I’m talking horses, cows, goats, sheep, llamas, dogs, cats and ferrets. I’d like to be accompanied by a herd of critters wherever I go on my extensive holdings. Also, “cars” includes bulldozers and forklifts, which I have an unholy love for. Gyrocopters, too, those are cool.
LPs
Similar to runcible spoon, but more. I’d have to have acres of mansion space, filled with intricate electro-mechanical objects on display. Difference engine. Grandfather clock. Baird scanning-disk TV. Airplane jet engine. Anti-tank sabot. Molten lead printing press. Doppler radar set.
Now that I think about it, I think what I really want is a physically touchable 3D Wikipedia.
Right now I end up perusing the hardware store every couple of weeks and buying stuff that’s on sale that I intend to use, but rarely do. If you keep me to under a million, I’ll just end up with the same type of stuff, just more and better brand names.
Camera gear. Lots and lots of camera gear. Lots and lots of lovely expensive camera gear. Mmmmm. I’ll have a Canon EF 600 F/4 IS to start with, please. Make that two. Ah, what the hell; I’ll take three.
Books.
Music.
Probably chase one of my dreams and learn to fly, and end up with a bunch of planes.
My own supercomputer, just for the bragging rights.
Land and houses, I suspect; I’d love to have a huge set of nature reserves all over the world, with tasteful yet comfortable accommodation for me and my minions.
Oh yes, and lots of cute suitably *unoccupied *panties, on my bedroom floor.
Comic books and off-road vehicles.
Random furniture. Book cases. Desks. Chairs, sofas, beds, tables, etc. I keep thinking I need a table here or a book case somewhere else and my wife has to bring me back to earth.
books, dvds, external hard drives, turtles, maybe plants
Books, music and candles. And Cash.
Guitars, amplifiers, books and tools.
Classic muscle cars. I’d need a '63 Vette, a '70 HEMI Cuda, A '68 Cobra and a '70 GTO, plus a stocked garage to care for them all.
Art, lots and lots of oils and sketches.
Fossils, rocks and Indian artifacts.
You’d be surprised how phlegmatic big dogs can be. My Neo puppy (who now weighs distinctly more than I do) will barely lift his head when I get up in the evening. If I pet him, he probably won’t even roll on his back to get belly rubs.
I’d end up with a lot of land between me and the rest of the world.
Me too, I already have more books and comics than I have space to store accessibly. I’m resorting to the loft, but it’s not easy access.
Time. If money were no object, I wouldn’t have to work and I could spend more time with my family and doing things I enjoy.
Oh- and “cute panties” wins the thread, hands down.
I want to change my answer 
Especially if you attach some frikkin’ laser beams to their heads!
I’m in for wristwatches and cigars. I’d have rooms dedicated to each.
And handsome underpants.
Acres. Wooded acres. Lots of them. With a lake. And a small mountain.
And a bunch of dogs that could run around and sniff things in the wooded acres.
Comic books and superhero action figures.
Art of all kinds. Since I’d have the room a lot of sculptures and big ass paintings. ( The paintings may not necessarily be displaying an ass but if it did that’s just bonus points.)
Stand up video arcade games.
stuff!