from DaemonEye Publishing
In Lands of Molokai we are using a wandering mosnter system with a few tweaks.
Each area/nation has it's own set of customized tables, according to terrain and, sometimes, subarea. The Forest table for the Emerald Hills is different than the one for the Hundred Kingdoms, ect.
Each encounter table has a set of group encounters according to the INHABITANTS of the area, mostly things along the lines of "patrols", "caravans", "traders", ect. Each of these is fleshed out in the same chapter, providing ample rp-ing opportunities (and minimal DM headache).
Each table also has NON-CREATURE encounters....many of whcih can be nastier than things with fangs

My play-testers have already come to fear the words "the light seems to dim and the air gets a pervasive bone-deep chill..."
Introducing a mechanic for wandering mosnter/adventure hook synergy. Still tweaking it. I've already run three adventures based off of it, with minimal work. Its a great tool if you are crunched for time, or your PCs decide to hose your prepared adventure.