In article <REM-2004may27-001@Yahoo.Com>, RobertMaas@YahooGroups.Com 
wrote:

this assumes that 'move to another star' is a potential niche

Once Dyson-sphere technology exists, putting a colony around another
star is definitely a potential niche. The only problem is getting
there. We have some ideas for doing that, but we aren't sure they'd
really work.

Nonsense -- "getting there" isn't an event, it's a gradual process.  
Take us for example.  After we've used the materials in the asteroid 
belt, and dismantled the moons of the giant planets, the obvious next 
targets are the Kuiper belt and the Oort cloud.  Our Oort cloud extends 
about three light years out from the Sun.  If Alpha Centauri has a 
similar Oort cloud, then its cloud overlaps with ours.  So by colonizing 
the Oort cloud, you're already starting to colonize the next star.  Just 
keep spreading, one convenient chunk of raw material at a time, and in a 
few hundred million years, you've colonized the galaxy.  No new kinds of 
travel are required.

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