A small rhombicuboctahedron is one of the 13 Archimedean solids. It has 26 faces (8 equilateral triangles and 18 squares), 48 edges, and 24 vertices.
To create a small rhombicuboctahedron:

Take a cube and cut down each of the 4 edges around the cube, leaving a regular octagonal prism. (Imagine a stack of stop signs.)
 Turn the prism on its side, and make 4 more cuts, just like before.
 Now take the 8 remaining corners, and cut them off, leaving equilateral triangle faces
A layout of the solid looks like this:
++
 
 
++ ++ ++ ++
  /\   /\   /\   /\
 / \ / \ / \ / \
+++++++++
        
        
+++++++++
 \ / \ / \ / \ /
  \/   \/   \/   \/
++ ++ ++ ++
 
 
++
This was one of the shapes that Rubik's Snake could be bent into.
A version of this solid where the bottom layer is rotated 45° is called a pseudorhombicuboctahedron or an elongated square gyrobicupola.
Source:
http://mathworld.wolfram.com/SmallRhombicuboctahedron.html