Bundles on Steam are a great feature. What you may not know is that Fantasy Grounds features one of the new bundle types that lets you pick up only what you haven't already grabbed from the bundle. If you are one of the many people who already owns any of the PHB, MM and DMG content on Fantasy Grounds and maybe even an adventure or two, you can get all the other adventures and settings for 25% off.
Not only will you get the remaining items at a discount, but you will get all future D&D items at a 25% off discount whenever you re-complete the set. This discount will also stack (to use a Magic the Gathering and D&D term) with any ongoing sales.
The latest release was the Curse of Strahd adventure and there are 2-3 new releases planned every year for D&D.
http://store.steampowered.com/bundle/256