Tomorrow is the second national Poem in Your Pocket Day.  This year I'm choosing a riddle poem, thereby increasing the likelihood that it will actually be read aloud.  Most people are probably familiar with Bilbo and Golem's exchange of riddles in The Hobbit; Tolkien modeled these on the riddle poems in the tenth-century Anglo-Saxon Red Book of Exeter.  This one is my favorite of Tolkien's (also the easiest to solve):

A box without hinges, key, or lid
Yet golden treasure inside is hid.

You can answer it in the comments.  And tell me, what you have got in your pocketses?