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I have been very lucky and have been able to travel this year. However, now that I am preparing to go back to the US, I realize that I have collected various small amounts of money (usually equivalent to $20–30) in a variety of world currencies. It is great to have such a 'coin collection', but since I'm travelling and living on a budget, I really would like to be able to actually use the money. What's the best strategy for changing various world currencies (e.g. Swiss francs, Thai baht, rupees, etc.) into dollars? If I go to a US bank where I have an account (e.g. Bank of America, Citibank) with foreign currency, will they be able to change it back into dollars?