  Samarium hexaboride crystallizes in a simple cubic structure (space group
#221, Pm-3m), but its properties are far from being straightforward. Initially
classified as a Kondo insulator born out of its intriguing intermediate valence
ground state, SmB6 has been recently predicted to be a strongly correlated
topological insulator. The subsequent experimental discovery of surface states
has revived the interest in SmB6, and our purpose here is to review the
extensive and in many aspects perplexing experimental record of this material.
We will discuss both surface and bulk properties of SmB6 with an emphasis on
the role of crystal growth and sample preparation. We will also highlight the
remaining mysteries and open questions in the field.
