Looking good. Boolean operations with terrains and objects are quite useful. I have used them for wounds in characters, to create a ruin from a bulding model, and so on. Terrains are also great for simple modelling by themselves when used in conjunction with heightmaps to define the shape. Here is an example where I made aSeafan (type of coral) from symmetric terrain and a photo of a real seafan. I have also used this for fences, a spiderweb, ...

Ciao

TD