Yeah, colonize every dirtball you come across.
Once you have PD5, PPBs, go for planet utilization, and convert those crappy planets into Optimal, 255% resources, breathable worlds  

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Get stellar manip and crush asteroids into planets.  Colonize them 
 
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Then build some Dyson spheres and colonize them 
 
 
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[This message has been edited by suicide_junkie (edited 20 April 2001).]