i downloaded all the chromatic shrutis here:
http://www.karnatik.com/shrutibox.shtml
and use them sometimes for practicing.
edit: practicing as described above by richard + playing scales, improvising
edit2: improvising with that shruti always makes me feel like charlie haden playing the song "malkauns" on the fantastic (one of my favorites) record "brown rice" by don cherry
)
edit3: please everybody buy that record
listen here:
http://www.amazon.de/Brown-Rice-Don-.../dp/B0000253J0