Some of the chiefest influences in my Motherlode game have been Terry Pratchett's Discworld novels. Though I have explored Appendix N as far as I could find through our public library system and swaths of used book stores (not to mention a pretty sweet trade with Scott of Huge Ruined Pile), I keep finding myself coming back to Great A'Tuin and the fantasy world balanced on his back.
First of all, the books are hilarious, not only for fans of fantasy but Anglophiles, cinema buffs and academics alike. I've spent many an hour just laughing at the assorted mottos of the Guilds of Ankh-Morpork and still think that if the BBC were smart, they should start adapting the Night Watch series into seasons of excellent television. But something about them also hits that part of my mind that is inspired by games like Moldvay Basic and Swords and Wizardry, and I think Pratchett explains it best in the introduction to the Art of Discworld:
The twist is that it is taken seriously; not taken seriously as a fantasy, but taken seriously as a world... So Discworld works, more or less. People plow fields, file things, make candles, deliver letters and babies, produce newspapers, perform daily the thousand minor miracles that keep a city fed. Magic has pretty much the same status as nuclear power: under control it is useful, perhaps even essential, but too much reliance on it comes with a disproportionately high price tag, and only a loony would use it to catch fish...That sort of darkly humorous fantasy ethos just seems to fit with my preconceptions about Basic D&D. Being clever and willing to improvise can be just as important as any martial prowess or arcane power; at Ankh-Morpork's Unseen University, learning how to manipulate magical forces is much less important than learning how not to use them.
Discworld also wears its modern influences on its sleeve, which I very much appreciate. I've never really understood the draw towards a purely medieval fantasy world, probably because I grew up on westerns, Hong Kong action movies and comic books. There should be black powder, even if there aren't guns; clockwork creations even if there's no steam power; a telegraph-esque service even without copper wires and electricity. Familiar elements like that seem to make it easier for players to understand how a fantasy world works, instead of having to approximate a brief history of hamlets in the Middle Ages every time the party wants to go to a tavern.
Hopefully, this influence will be reflected in the game and make Motherlode something a little to the left of a typical fantasy town.
Art by Paul Kidby. Some of the best page-to-picture translations I've ever seen.