A city i've been working on for about 16 months now, used to be 100% survival, when I made all of the cobble structures, after that I made it creative, and all of the other towers were built. City also features many many subway lines, complete with stations and over 3000 blocks of track, a freight terminal, two banks, two shopping malls and an arch bridge (outside the picture).
It will never be quite finished, as I'm always adding more onto it, but I guess it's about 30% towards what I want it to be. Built using versions 1.6.2 - 1.0.0 (The world file takes up about 2.2GB, so I'm not going to convert the world to 1.4.2, since it'll take about 6 weeks =D)