  Skyrmions are particle-like topological excitations, studied in various
condensed matter systems and models of high-energy physics (HEP). They occur as
stable spin textures in certain planar magnetic materials and as configurations
in chiral nematic liquid crystals, having been originally proposed as model of
atomic nuclei. Since magnetic Skyrmions can be accelerated with a current, they
have the potential to encode bits in low-power magnetic storage devices.
Drawing on techniques from HEP, we demonstrate that magnetic and liquid crystal
Skyrmions interact like orientation dependent, localised particles, explaining
previously observed Skyrmion behaviour. This interaction motivates the
construction of Skyrmion bags: textures of high topological degree which we
realise experimentally in liquid crystals, and in magnetic materials by
computer simulations. These Skyrmion bags configurations are nested multiple
Skyrmions, which act like single Skyrmions in pairwise interaction, and under
the influence of a current in magnetic materials. These results emphasize
equivalent Skyrmion behaviour in different physical systems, and suggest new,
high-density magnetic memory storage devices based on Skyrmion bags.
