  An orthotube consists of orthogonal boxes (e.g., unit cubes) glued
face-to-face to form a path. In 1998, Biedl et al. showed that every orthotube
has a grid unfolding: a cutting along edges of the boxes so that the surface
unfolds into a connected planar shape without overlap. We give a new
algorithmic grid unfolding of orthotubes with the additional property that the
rectangular faces are attached in a single path -- a Hamiltonian path on the
rectangular faces of the orthotube surface.
