[spoon]

You could make a ship hull (the Colonizer) that costs maybe 100,000 organics to build and give it these abilities:
- Colonize - (planet-type)
- cargo
- Reduced Maintenance (90% or so)
- bridge
- maybe some other stuff as needed (life support? crew quarters?)

Then make a hull type (the colony Mothership) that can build at 0 minerals, 0 rads, and 100,000 organics. This Mothership can then go from planet to planet making colonizers. (You can of course reduce the mothership build rate if you want it to take more than 1 turn to build a colonizer).

Haven't thought it all the way out - might be some way to abuse it, maybe with Organic Tech?

-Spoon