To what extent are solar energy back packs for sale or otherwise
available?  A solar back pack is described as an  apparatus designed
specifically to carry a portable solar energy system (i.e., a
photovoltaic solar panel, battery, and charge controller) by a human
being to be able to power electrical appliances where normal
electrical outlets are not available. For example, the Solardyne solar
power pack (www.solardyne.com) is advertised as the world's first
personal utility that you can take anywhere.  Are there other such
portable solar packs available?