I need to pick the brains of all you creative board memebers.

Here's the situation:

I'm giving a cash gift to a friends daughter for her 13th birthday. Cash is the best thing because she LOVES clothes but is very tall(I think she's around 5'6") and thin(oh, to have her problems, heehee!), so has a hard time finding clothes at many stores.
Anyway, I'm thinking $15 is probably a good amount but I want to come up with a cute/fun/clever way to present it that won't break the bank. Money in a card is nice but there has to be something better.
The only other time I gave money to a kid for their birthday was to a boy who was turning 5 and I gave him $10 in Gold Sacageweia(sp?)dollars and he thought it was a pirates treasure. Pretty sure that won't work this time.......

Please help me! I'm fresh out of ideas. Also, if $15 is not in the right ballpark, please clue me in as to how much is right.

Thanks so much!

Oh, her birthday is in 2 weeks so I have some time.

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