Box Thing by Quandtum Blender Version: SVN r42667 Released under license is CC BY-SA.
A model I did a long time ago for a project that never got wrapped up. Was intended to be the bad guys in an animation. These guys were intended to "bobble" about in groups like jellyfish, casually moving but grabbing up all they could with their tentacles. The model is fully rigged and constrained, however, the rig is a bit rough and the IK spline doesn't always update as you move the armature target points, but if you tab into the mesh and back out it will update. The boxes for each of the legs is a switch from the tentacles stretching to the target vs. not stretching.
More details on the animation if you are curious can be found here:
Textures were hand painted using Blender procedural and GIMP with exception of the recycling symbol which can be found here (public domain, no copyright):