Renaissance Ink has had “flocking gels” for sale for several years, but I was never sure what they were, or what to do with them. This site has a tutorial on how to use the stuff. Looking closely at the photos, I think I can safely say that flocking gels are textured gesso, of the type that you find in the ladies craft stores, such as Michael’s. I’ve use the gritty gesso to texture the sides of my foamcore houses, and the fibrous type to make thatched roofs.
This video shows how to use basic packing inserts to make effective Necron Tombworld terrain for Warhammer 40K.
Ryan Scow has an article on making balsa strips look like realistic timbers.
The City of Solis website has some good looking, hand drawn banners that you can cut out and use with your Warhammer, Chronopia, or other fantasy armies.
Here’s a video with advice on building modular catwalks. The techniques also can be used for a variety of science fiction projects.