MAiLmeART is a competition where entrants have to create works on art that will be posted. The main rule is simple: the entry must have travelled so the postman can see the art. Entries are also welcomed from around the world.
You can post at many items as your want, although one a month is the limit, and you need to include your e-mail on your item of post. The post art also has to be child friendly as DeLito says "sometimes my son picks up the post".