Xath
Moder-gator
genshou said:For me, it'd have to be Stronghold Builder's Guidebook + Arms and Equipment Guide. Couple those two books with Medieval Demographics Made Easy, and you can create kingdoms and populate them with castles, ruins, and itinerant magic item merchants. Which is, BTW, such a ridiculously fun activity that it has even surpassed Pointless NPC Mass-Production (tm) in my list of hobbies.
I use both of them frequently. I love building cities and populating them as well.

I'm....obviously a party animal.