Check out the quirky paint job on these !predator aliens:
You may be thinking that this is a lazy paint job, but there is a method to my madness. Remember that these guys are supposed to be cloaked. Painting them the same colors as the ground cover means that they blend in with the game board itself:
Which brings us back to the real reason that I prefer the terrain tiles method of battlefield construction to the drop cloth method. You can use the exact same paints for the field and the figure bases, and that allows precise color matching for effects like this.