I don't get why people ask their parents if they can mail stuff. You don't need your parents permission to send money to Badspot. Go to the post office, put money in an envelope, and mail it. You don't need an ID, you don't need your parents to sign a waiver, you don't need anything. Except $20 I guess and a bit extra to buy stamps or pay for postage. You can send mail at any age. The staff at the post office are very helpful and will basically do everything for you as long as you've got a properly addressed package.
I got a free key by sending a birthday card to Bisjac. It cost $7 to send it and my parents didn't know. Ok, well, I did say "Hey dad I'm walking to the post office, be back in a bit" and he said "okay." Nobody cared what I was mailing. All you have to say is "I'm going to take my bike around the block" or "I'm going for a walk be back in a bit."
