Bukkit

As of 2.3.1, Apocalyptic's Ravaged™ world generator can generate Schematic files! To use this, create a folder called "schematics" in the Apocalyptic folder. Put schematic files in here, then edit the Apocalyptic/worlds/your-world.yml to add these schematics, in the form:

schematics:
    my-schematic: 100

my-schematic is the name of the schematic file, and 100 is the inverse frequency, as in 1/100 chance.

Here are some recommended schematics, created by CalamityGreen.

Dropbox