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Emma Watson was blissfully ignorant about the size of her bank account until it was handed over to her on her 18th birthday last year. The "Harry Potter" star tells the August issue of Elle UK that she had no idea that playing wise witch Hermione Granger had netted her a fortune in the tony neighborhood of $16 million.

"My dad never told me how much money I was earning," explains the actress, who poses for the mag in a sleek, rib-breaking corset and Angelina Jolie-esque cat-eye makeup. "Then, when I hit 18, he was like, 'I want you to be able to understand that your money isn't some kind of abstract concept. I want you to have a feel for what it's worth and what you can do with it."

To accomplish that, she attended bank-run classes to learn about responsible spending.

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"The course was interesting, I'm glad I did it, but the truth is I'd just like to pretend that [the money] doesn't exist," says Emma, who will soon wrap the "Potter" franchise and head off to college (Columbia University is tipped as the current front-runner). "It's amazing how many children are aware from such a young age about money being important or supposedly impressive. Around the age of 13 or 14, kids used to come up to me and say, 'You the girl on 'Harry Potter'? How much do you make?'"

According to the refreshingly sensible starlet, her biggest extravagance is a nice meal every now and then.

"I really don't have time to spend my money," she shrugs. "Sometimes my bank manager calls me to say, 'You haven't used your card in a while and now you're using it -- no one's stolen it have they?!'"

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That's not a problem her co-star, Rupert Grint, appears to have.

"I don't really handle the money -- I never see any of it in physical form," the ginger-topped Ron Weasley explains to the London Daily Mail. "It's only in the past few years that I've had my own credit cards and can buy pretty much what I want."

And what the actor wants is what you'd expect from any 20-year-old boy-man with overflowing coffers and no concept of retirement savings.

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His splurges have included arcade games, a hovercraft and a garage-full of vehicles, including a 1950 Chevy pickup, a bright orange Range Rover ("People rib me that I only bought it because it matches my hair") and a tricked-out ice cream truck, his personal favorite.

"I probably spend more time driving around in that van than anything else," says Grint, "and if the acting suddenly comes to a halt, I can't imagine a better job than being an ice-cream man. I love going on eBay and buying accessories for the van, things like light-up cones that I've stuck on the front."

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