left to right: Fitz, Tyler, and Ella

Dog-cycles!  There are similar products available, but my solution is better (read:cheaper).  Have a slightly run-down bike sitting in the garage not getting much use?  Up-cycle (heh) it into a dog-cycle.  Running your dogs while you pedal (or are pulled)) is great - your pups get far more vigorous, satisfying excercise in less time than a walk.