Ruby on Rails Application - Essentially a mixture of Google Wallet and PayPal functionality.
Misc Features:
Create/Delete/Edit user functionality | Admin user accounts with special privileges | Grant credit card access to others | Ability to send/receive funds | Form validation checking (making sure forms are submitted securely, valid telephone number format submitted, valid password length, etc) | REGEX Card Algorithm to figure out which type of credit card type has been entered (Visa, MasterCard, etc) and to make sure it is a valid card number | Cookie logging |