The question Has anything ever executed an orbit change such as between ISS and Hubble? has a in interesting answer. It made me wonder, would something like the (patented) Lunar Flyby technique use less detla-v than a direct, propulsive inclination change of about 23 degrees?
edit 1: Let's say it's not a delicate communications satellite, so aerobraking is allowed for part of the circularization at the end, and there is no rush, a transfer time of maybe six months would be OK.
edit 2: Hubble to ISS is OK too. Starting at the lower of the two inclinations is probably going to be necessary if this is at all possible.
note: something like this was used to correct the orbit of PAS-22, making it the first commercial spacecraft to reach near-lunar space if I understand the Wikipedia article correctly. It says:
Using on-board propellant and lunar gravity, the orbit's apogee was gradually increased with several manoeuvres at perigee until it flew by the Moon (9) at a distance of 6,200 km from its surface in May 1998, becoming in a sense the first commercial lunar spacecraft. Another lunar fly-by was performed later that month at a distance of 34,300 km to further improve the orbital inclination.
These operations consumed most of the satellite's propellant, but still much less than it would take to remove the inclination without the Moon assist manoeuvres.
(9)Space Daily's Book Reveals How Hughes Saved ComSat In 1997
Would a maneuver involving the moon also be lest costly in delta-v than a direct plane change if transferring from the Hubble to the ISS?
For reference, here is Figure 2 of US6116545