powerful geography software?

I'm looking for recommendations for geography software that can let the user manipulate data for arbitrary geographies (Earth, Mars, fictional planets, etc), including visualizing geographies with differing hypothetical variables and conditions (for example, what certain landmasses would look like if the sea level were 50 feet higher, including calculating ways water would "spill" into previously-dry areas... or what landmasses will look like after a few hundred years of continental plate-drift)... is there any free software out there that does this, or is this domain still mostly in the realm of proprietary software?

So far the only thing I have that vaguely does this is the game SimEarth... buuut that's not really exact enough for what I need to calculate.  And it's more of a game/toy than an app :3

What you're optimistically calling 'geography' software is actually a collection of a number of different types of software, including mapping, 3-D modeling, complex animation and fluid dynamics amongst others (at least for the quality you're implying you need).  If you did manage to find what you need, you'd probably have to buy something a bit special to run it on.....

>>1
For a second, I thought it said "pornography software".