[gregebowman]

Originally posted by Guille:
Build mineral, organic and radioactive storage facilities. They allow you to have more than 50000.

Keep building those storage facilities. Research Cargo to the max (level 3), and then start putting them everywhere. Those tiny planets that hold only 1 facility? That's what I use them for, at least most of the time. Especially after I research Ice Colonization and Gas Colonization. You'll suddenly notice a lot of those tiny suckers around.