I lost my most gratuitous single-player game in a HD crash a few months back
I was only 60 or 70 turns from completing a Cultural Centre on a Ringworld, too.
Never mind, I've started again, using Andres' latest and greatest set (The one with the Geiger portrait).
Proportions again, max AI bonuses and difficulty, only this time it was on a "no warp points" map, so i had to research stellar manip up to level 2 or 3 before before I could even expand beyond my home system! By the time I did, the Jraenar had dedvelopped their own warp openers and were sending 40-ship fleets against my 10 ship fleets and destroyed half my empire. My stellar manip ships were mothballed, my economy almost bankrupt and my weapons tech pathetic.
After losing masses of ships & planets I've finally managed to get my borders back under control - all warp points lead straight to breathable planets with massive planetary shields, heaps of troops and massive-mount shield killer/ripper beam/engine killer wep plats. Soon I can start to rebuild my economy and push back, then finally begin work on a ringworld and a ultimately a CC.
Reckon I'll get there before turn 2000, although I forgot to take temporal for the super spaceyards.
Epic is just the beginning...
Gratuitous
(except for my 'nature preserve' region which is mostly in the lower-right of the map, where I haven't stripped the atmosphere off any of the planets or capped the stars)
You gotta love a game like this when you can start it a year ago and still be playing a year from now. 
Linear Mode
