Project Gutenberg is one of those amazingly cool things that are going on out on the web somewhere that you might have heard about once or twice, but a lot of folks never really have given it much attention. I think that's kind of strange and so I wanted to point out a few of the very useful things that you can find over on the Gutenberg site that might be of interest to DMs in terms of really good (and really free) literary references that you can use to spice up or weird out your gaming, or just read for the hell of it. Some of this stuff is really, really good. If you know where to look. Which is why I put togther this quick and easy guide to some of the stuff that I found most useful or interesting in the course of working on my setting.
Arthur Machen
The Great God Pan
The Hill of Dreams
The Great God Pan is not as well known as The Angels of Mons, but it is a very well-done story of occult horror that really demonstrates a sense of overwhelming horror and the terrible consequences of confronting things beyond mortal ken. It's not just something that a Call of Cthulhu fan ought to read. The underlying premise could be retooled for any number of variations and involve any sort of entity, not just a horny old Greek god. It's also interesting in that this story involves a woman who makes an impression on society despite being not-quite-human, instead of another spineless hick from some podunk town like Wilbur Whately. Reading Dunwich Horror back-to-back with Great God Pan might be damaging to your sanity.
Edgar Allen Poe
The Raven
First Project Gutenberg Collection of Poe's Stories
The Masque of the Red Death is one of my all-time favorite Poe stories and a strong influence on some of the Great Houses in Riskail. The Cask of Amontillado is a great scenario-seed. "For the love of God Montessor!" Then there's the Murders in the Rue Morgue; who doesn't love a monkey? Just because it's a murderous Orang-Otang doesn't mean it doesn't need a hug. Poe is awesome, and his works are an excellent source of ideas for all sort sof things ranging from plots, to traps (Pit & Pendulum), to setting-details, and on and on. I am sort of surprised that there isn't a Poe RPG out there, but then maybe Marcus Rowlands did one as part of the Forgotten Futures project (which is in itself a wonderful thing to take a look at for all sorts of ideas).
Ambrose Bierce
An Incident at Owl Creek Bridge
The Damned Thing
Before M. Night Shyamaln's Sixth Sense, there was Bierce's classic Incident at Owl Creek Bridge, whih could easily be converted into an effective game scenario, if you didn't mind player character ghosts. Of course, if you didn't read this in high school, you could always watch the Twilight Zone episode based on Bierce's story. The Damned Thing is all about a critter that is of a color that the human eye cannot see. Several other authors have since lifted this idea, filed-off Bierce's serial number and made it their own, and why not? It's in the Public Domain, so this is the kind of things that people Can borrow from, lift freely, and make their own.
Jules Verne
From The Earth to the Moon
Mysterious Island
I just downloaded a copy of Verne's The Underground City as I've never run across it before. Maybe it'll spark a few ideas as I flesh-out the subterranean regions around the Low Esplanades. You can find a copy of 20,000 Leagues Under the Sea, and quite a few other works by Verne, and his work is very much worth your time and effort because he is extremely inventive yet did his best to stick to what the science of his day considred plausible, unlike Wells who invented a substance that allowed his characters to negate gavity in order to go to to the moon. Verne did things the hard way and it is often well worth the effort to get through the front-end of his books. But it will require something of an attention span.
H. G. Wells
The War of the Worlds
The Island of Doctor Moreau
While I prefer Cordwainer Smith's approach to underpeople, Well's pseudo-hybrids created through surgery and torture ("The House of Pain"), are both horrific and yet exactly the sort of creatures that a mad wizard or insane genous would sped their time creating, and three-legged Martian war machines are just plain cool. Their Public Domain, so why not use them in your game? There is a lot of H. G. Well's stuff there at Gutenberg, including a Free copy of Little Wars, his miniatures wargaming rules, and some of his Socialist stuff, The Invisible Man, The Time Machine, and more. Morlocks are great monsters; underground-dwelling degenerate industrialists who prey upon the stupid hippies. Now how fun is that?
Sax Rohmer
The Brood of the Witch Queen
The Insidious Doctor Fu Manchu
Far from politically correct and quite blatantly, shall we say "of it's time" in regard to racial issues, Rohmer's stuff is good pulp fiction and by that I mean a real time-waster of a book that reads like they sould ahve been made into a series of animated adventures already. If you read Marvel comics in the Seventies, you'll recognize all sorts of stuff
Algernon Blackwood
The Willows
The Wendigo
Blackwood is a real treat to read. He knew a great deal about which he wrote and his John Silence stories are some of the best in the entire genre of Occult Detectives. The Wendigo is a great story to read right before a skiing trip, really. Like reading an accout of the Donner Party just before driving across the Rockies during the winter. Um tastes like chicken.
William Hope Hodgson
The Night Land
The House on the Borderland
Lovecraft was a big fan of Hodgson's, but despite the nasty pig-people, House on the Borderland is well overdue for a re-write. The Night Land is Olaf Stapledon style far, far future stuff that is still quite inventive and interesting, which most other stuff half as old as it are not. Hodgson's Carnacki stories are aweome and I expect to read about Electric Pentacles in Planet Algol very soon.
Edgar Rice Burroughs
At The Earth's Core
Warlord of Mars
Most of the Barsoom books are there for the taking at Gutenberg, but the Burrough's estate still retains rights to the names of the characters, etc. So while the stories are yours to take for free, the names are not. Copyright gets a bit weird. If you want something that has a lot of the same overall feel as Burrough's martian adventures, you might check out Athanor as a very well-done Swords & Wizardry-based setting that packs a really mean wallop like a certain genteman adventurer whose name is not in the Public Domain.
Sir Arthur Conan Doyle
The Lost World
The New Revelation
Besides the extremely name-recognized Sherlock Holmes, Doyle produced a lot of stuff, the Lost World having been converted into movies and a TV series might ring a bell of recognition, but did you know about Doyle's fascination with Spiritualism? Yep. Check out The New Revelation sometime. Maybe Holmes wasn't the only one using a seven-percent solution? There are some nifty things in there, but then I read Blavatsky at an early age.
Besides all the literary (or at least genre master) heavy-hitters listed about, there is a ton of old Historical resources at Gutenberg, from Baron Acton's Lectures on the French Revolution, to an account of WWI-era airplanes and submarines, to an account of the Arts and Crafts in the Middle Ages, and more. Those were all drawn from the section under 'A.' You can also find translations of works by Plato, Titus, and if you want you can get a free copy of Machiavelli's The Prince.
It's worth digging around, you'll never know what you might find and it's free. Some of the stuff is also available in audio format, if you'd prefer to listen to some of these tales instead of read them, which can be a great time-saver or life-saver depending on your situation. They can always use donations and they need volunteer proof-readers and the like, so if you're inclined to lend a hand they'd be glad to have some more volunteers.