The OMad blog has an article on converting Lord of the Rings plastic figures. Learning techniques such as these will come in handy, given the large number of plastic figures now in the offing.
modeling
A Futuristic Bunker From Miniature Bases
Toposolitario has a tutorial on making a futuristic bunker out of spare miniatures bases.
Making Plasticard Movement Trays
The Tabletop Terrain site has a little, but useful article on making movement trays for your figures. This is particularly useful for games like Warhammer Ancients and the new Lord of the Rings big battle game, where large numbers of individual figures are maneuvered about.
Elven Autumn House
Terragenesis has an illustrated article on the construction of a beautiful elven house for 28mm gaming.
Making Wooden Crates
Terragenesis has a good illustrated article on making wooden crates for 25mm / 28mm gaming.