Look at Blender and MediaWiki (the software running Wikipedia). They’re both FOSS and are developed and maintained by volunteers, backed by the end users. They’ve become such a big part of people’s lives, both professionally and privately, that they’ve become the mainstream choice.
Me as well. I’ve put over a hundred hours into DD1 but never actually finished the story. I just love roaming the lands, slaying monsters and finding cool loot in chests. Absolutely love the game, and I’m more excited for DD2 than anything GTA.