TerraGenesis has an article on making palm trees from toothpicks and scouring pads. They look pretty good, and would be just the thing for those Flames of War desert and pacific scenarios.
Modeling
Weathering With Foam
Dark Future gaming has a post on using bits of foam to weather a 40K vehicle. The technique could be applied to almost anything, though.
Making Heavy Foliage Scenery
The Corbania Prime Blog has a nice illustrated tutorial on making heavy — jungle — foliage terrain pieces.
Tray Fillers
The Wargames Table blog has a good idea for filling in the blank spots on a movement tray.
Basing Miniatures Tutorial
The Land of Counterpane blog has a nice piece on basing figures. We all have our methods, but it’s nice to see how others do it.