My personal favorite was Canopus by Clairvision astrology, which is no longer available :(
So, after some searching, my new favorites are,
AstroLog - free software. it takes some getting used to, but once you do, it is VERY useful. It calculates dozens of charts with interps. Good accuracy too.
Zet 8 Lite - free software. Very nice substitute for Canopus. Easy to use graphics. Combining this and Astrolog together - well I don't have to pay a penny & get everything I want!
These can all be easily searched on
www.google.com and downloaded for free. Not huge files either.
A good website:
www.grupovenus.com - online site that does free calculations and interps. It's a bit like
www.astro.com, but has a LOT more free stuff on it!! I really like it.