One of the downsides of an old iron habit, is figuring out how to safely and securely move the large machines around.  Machine skates (below) are nothing new, however buying a set of them is prohibitively expensive for a hobbyist.  Luckily they are easy to make with some decent bearings and scrap steel.  I made two of these.  They are incredibly strong and allowed me to push around the 2000 pound lathe by myself.  One caution, always use something between the skate and the machine (small piece of wood, cardboard, etc.).  Steel on steel can be quite slippery.