Abstract: A computer-implemented system distributes digital content (such as electronic trading cards) to users and receives such content back from the users. Consideration, such as rewards, may be provided to users in exchange for the digital content they return to the system. For example, a redemption program may provide a reward to users who redeem a specified group of electronic trading cards. Users may trade digital content with each other, and a user who returns a particular unit of digital content need not be the user to whom the digital content unit was originally distributed. Cards may be individually identifiable, enabling both the original recipient of a digital content unit and the redeeming user to be identified. Each user may use the system to keep track of the digital content units that the user has returned to the system so far.

Abstract: A composition is provided that is suitable for topical administration for the treatment of skin to reduce the harmful effects of ultraviolet radiation impinging on the skin, the composition comprising acetylsalicylic acid and sodium bicarbonate. Also provided is a method for treating skin to reduce the harmful effects of ultraviolet radiation impinging on the skin comprising topically administering to the skin a therapeutically effective amount of a composition comprising acetylsalicylic acid and sodium bicarbonate. Also provided is an aqueous composition suitable as an additive to a composition of cosmetics comprising acetylsalicylic acid and sodium bicarbonate. Also provided is a method of manufacturing a cosmetic composition, comprising obtaining an aqueous composition that includes acetylsalicylic acid and sodium bicarbonate, and combining the aqueous composition with cosmetic ingredients to create the cosmetic composition.