Death From Above
After 51 it did get ridiculous. But I was able to hold out, I set myself up for an epic showdown. All researchs finished, EMPs, Freeze Turrets and Obliterators on all of the planets outskirts. They were backed by dozens of Laser turrets and enough Power Plants to power them all. I terraformed the planet so it was a productive money/power provider. Most of my mines were destroyed by the never ending onslaught of space armada, but the money I gained from killing them was more than enough to keep buying power plants. The game eventually kept freezing constantly but I still held on.
There was no way I was letting that grumpy news reporter from Futurama take my planet, even if he had dyed his skin. On and on it went... til finally one suicidal bonzai attack upon my city while my defences were down. A bright light and it all went away.
1,885,689 Points.
I think level 51 in Nan is the actual time limit of the game. The intention is to reach a pop, but dammit, how will a large population stop the genocide?
OK game... but needs work. Still fun for 20 minutes or so.