  We consider general supersymmetric solutions to minimal supergravity in six
dimensions, trivially lifted to IIB supergravity. To any such solution we add a
travelling-wave deformation involving the additional directions. The deformed
solution is given in terms of a function which is harmonic in the background
geometry. We also present a family of explicit examples describing microstates
of the D1-D5 system on T^4. In the case where the background contains a large
AdS region, the deformation is identified as corresponding to an action of a
U(1) current of the D1-D5 orbifold CFT on a given state.
