I knew that talc (baby powder) was good for greasy hair but I never really used it, now I swear by it! I conditon my hair so much now, even right in the roots.
After a shower, when my hair has air dyed I put talc in it. You need to do it the right way or you may end up with white hair. Bad times.
I do this everynight so if I do get a bit of a white problem it has hopefully rubbed off on my pillow or my hair oils have soaked it up. Part you hair and sprinkle on small amounts, one section at a time.
My hair never gets as greasy as it used to and sometimes I can even skip a hair wash! :D