  This paper studies giant magnons in CP3, which in all known cases are old
solutions from S5 placed into two- and three-dimensional subspaces of CP3,
namely CP1, RP2 and RP3. We clarify some points about these subspaces, and
other potentially interesting three- and four-dimensional subspaces. After
confirming that E-(J1-J4)/2 is a Hamiltonian for small fluctuations of the
relevant 'vacuum' point particle solution, we use it to calculate the
dispersion relation of each of the inequivalent giant magnons. We comment on
the embedding of finite-J solutions, and use these to compare string solutions
to giant magnons in the algebraic curve.
