The only legitimate methods of attaining a cape in "Minecraft" are through attending official "Minecraft" events such as MineCon, or receiving it directly from the developers, Mojang. The official MineCon site allows users to register for events and potentially claim serial codes for downloading an authorized cape.
To prevent players from purchasing tickets for the capes alone, only players who physically attend MineCon receive capes. Mojang distributes the codes through email after the event. Children 3 years of age or younger receive free admission to MineCon, while those age 14 or under must parents or guardians accompanying them.
The "Minecraft" mod "MCCapes" allows users to choose a wide variety of community-made capes for in-game display. Users who install the mod can see the chosen capes of other players.