This tutorial shows how to make modular cave tiles that also serve as hills for wilderness games.
modeling
Making Flocked Magnetic Unit Stands
The WAB Corner Blog has a nice post on making terrained magnetic bases to hold four figures based individually on washers.
Making Textured Paint For Foamcore Buildings and Ruins
This video tutorial covers making textured paint for foamcore buildings and ruins.
Modeling Wheat Fields From Door Mats
Iron Mitten has a photo tutorial on making wheat fields from door mats.
You can get the textured door mats in a variety of colors and textures, so this technique should be usable for a lot of different types of fields.
Pin Vice Tutorial
Instructions on how to use a pin vice