I don't often rave about any individual offering from any particular company, though I am keen to point out companies who do a great deal of great work, but this post will be different. I have been keeping an eye for some time on the various Dungeon Dressing posts from Raging Swan and thinking about what a fantastic collection of tables and GMing tools they are. Last week, I decided to plunk down the money for the PDF compilation "GM's Miscellany: Dungeon Dressing." I have spent quite a bit of time with it since and it is page after page of fantastic material that can be used as is for quick dungeon/location preparation but also as multifaceted springboard to worldbuilding. I cannot recommend this tome enough. Check out the details here on the Raging Swan website where you will also find tons of sample pages and content breakdowns.