Islands
Termos

lua mapgen featuring tropical islands and vast ocean

Citygen
BuckarooBanzai

city mapgenerator

Magma Conduits
FaceDeer

Removes default mapgen lava and adds widely-spaced vertical lava "veins".

Mistere's Adventure Map Island Creator
MisterE

A 1000x1000 canvas for your imagination

Watershed
paramat

A river / mountain range mapgen

voxelmanip experiments and remade math mandelbox mapgen
chaosomnium

Voxelmanip mapgen with strange layered zone experimental mapgens.

The Confluence
MisterE

A luamap example - a small (500x100x500) Island in the middle of the ocean with 4 rivers that run from the center to the sea.

Aqua World
NovaX

Generate an underwater world with deep water, sand, and sandstone.