  In joint work of the author with Stefan Witzel, a procedure was developed for
building new examples of groups in the extended family of R. Thompson's groups,
using what we termed \emph{cloning systems}. These new Thompson-like groups can
be thought of as limits of families of groups, though unlike other limiting
processes, e.g., direct limits, these tend to be well behaved with respect to
finiteness properties. In this expository note, we distill the crucial parts of
that 50-page paper into a more digestible form, for those curious to understand
the construction but less curious about the gritty details. We also give one
new example, of a cloning system involving signed symmetric groups.
