The TGPGuiLib is a cross platform user interface library for Terragen plugins.
WaterWorks is a set of Water Effects plugins.
For Export Only is a set of Terrain export plugins.
Solaris is a Lighting Accessory plugin which sets the position of the Sun based on a position on the Earth and a time.
Mac examples from The good-looking textured light-sourced bouncy fun smart and stretchy page This page has some Mac versions of the examples on The good-looking textured light-sourced bouncy fun smart and stretchy page. I've been following along with the site for a while now and have made a few of the examples. You can download both the apps and the source. I should update all this, most of it isn't Carbonised.
From the pre Terragen Mac Dark Ages... Here you can find some pictures I've created using Terragen, an excellent landscape generator/renderer. As it is currently a Windoze only program, I'm using it on my Mac using a PC emulator.
Jo's Dumbass Terragen Gallery