Some literary suggestions:

Empire of the East from the tetralogy by Fred Saberhagen; the Book of Swords series, originally conceived as setting for a planned computer game if memory serves, is backstory

Well World from Midnight at the Well of Souls and sequels by Jack Chalker

Viriconium from The Pastel City, A Storm of Wings, In Viriconium and Viriconium Nights by M. John Harrison

Bas-Lag from Perdido Street Station, The Scar and Iron Council by China Mieville

Ambergris from The Hoegbotton Guide to the Early History of Ambergris, by Duncan Shriek (chapbook, also collected in City of Saints and Madmen) by Jeff VanderMeer

I must mention the great Abe Merritt, in particular:
"The People of the Pit"
The Moon Pool
The Face in the Abyss
Dwellers in the Mirage

H.P. Lovecraft of course is more famous today; his tales provide a great canvas across time and space (including the Dreamlands).

The general concept of a 'multiverse' seems up the alley, and Farmer's World of Tiers series has been alluded to. A couple of books by Bob Heinlein come to mind: Glory Road and The Number of the Beast.

Jack Vance's Dying Earth series is classic. A Quest for Simbillis by Michael Shea is an authorized (but now non-canonical) addition. Pelgrane Press published a Dying Earth RPG line.

The Talislanta game, now legally free online in several editions, was inspired by various Vance works including the Tschai (Planet of Adventure) series.

The Moon Maid, The Moon Men and The Red Hawk make up perhaps the greatest work of Edgar Rice Burroughs' career. If you assume that Pellucidar, Caspak, Poloda, Tarzan's Africa, John Carter's Mars, and Carson Napier's Venus all co-exist, then you've got TONS of adventure material on tap.

Michael Moorcock's A Nomad of the Time Stream trilogy (Warlord of the Air, The Land Leviathan and The Steel Tsar) explores alternate 20th centuries.

The Dancers at the End of Time (An Alien Heat, The Hollow Lands and The End of All Songs) is extremely far out.

Cynosure, the pan-dimensional city of the Grimjack comicbooks, was (with modification) my D&D game setting in the 1980s.

The world of The Goblin Reservation by Clifford D. Simak might make for an interesting campaign.

That of The Wine of Violence by James K. Morrow would I think be more for a short visit.

I remember Zelazny's Lord of Light as a great story. The question is what kind of game scenario to present, for instance whether the players should be 'gods' or among the medieval masses.

C.S. Lewis's Out of the Silent Planet, Perelandra and That Hideous Strength would definitely be out of the ordinary.

Speaking of Burroughs, I always thought an RPG treatment of "Beyond Thirty" would be fun.

Quote from: Hybridartifacts;861419Never knew that - interesting.

That's where Aspects come from, from what I've read.

Quote from: Phillip;861690Cynosure, the pan-dimensional city of the Grimjack comicbooks, was (with modification) my D&D game setting in the 1980s.

I've seen the RPG book 'Nexus: The Infinite City' often described as being very reminiscent of Grimjack's setting.
It always reminded me a bit of Bugtown from the 'Those Annoying Post Bros' comics.

My DCC "Last Sun" Campaign is inherently silly, but it's also a coherent world.  Nothing in it happens without explanation.

Sooner or later it'll be an RPG setting, either for DCC or something else.

Zelazny's "Jack of Shadows" -- a world half light and technology, half darkness and magic -- seems like a general idea ripe for game treatment. A friend worked on something along that line, based on the novels Changeling and Madwand.

Has anyone mentioned Jason Richard's BREACHWORLD?

BREACHWORLD
http://www.breachworld.com/

It's RIFTS D6 effectively, but somewhat lowered powered. Its very playable and certainly not silly. I am looking forward to Jason expanding the setting.

EDIT: it's totally possible I posted this previously in this thread. Enjoying Austrian vodka this evening while posting buzzed and headbanging so I apologize if this is a double post.