Best multiple-system-friendly RPG supplements?

[Aus_Snow]

Or hey, 'system neutral' if they really are. Whichever.

Are there any books (or PDFs) you might find yourself turning to, regardless of the system you're planning on using at the time?

 

[Wraith101]

A lot of the Kingdoms of Kalamar stuff is excellent setting fluff with very little crunchwise. I use them as constant inspiration for my games, no matter what the setting.

All the Magical Medieval stuff my XRP is great too, a great series that apply no matter what the system (ok, maybe fantasy only!)

I also steal a lot of stuff out of The Book of the Righteous for other fantasy games as well. My last Burning Wheel game had several of the churches prominently featured.

 

[Glyfair]

A lot of the Kingdoms of Kalamar stuff is excellent setting fluff with very little crunchwise. I use them as constant inspiration for my games, no matter what the setting.

Especially the pre-d20 adventures and supplements. The rules info that appears is pretty much the "generic D&D" stuff that was popular prior to the OGL.

I also find the "Citybook" series to be pretty good.

Of course, I swear by the non-systemic products from Paizo (item cards, flip mats, etc.)

 

[Viktyr Gehrig]

I don't play GURPS, I don't know how to play GURPS, and I've never once even read the GURPS Basic Rules.

But I've got a bookshelf full of the sourcebooks. Money better spent than many of the books I've purchased for games I actually play.

Though... now that I've said it, it makes me want to actually have a look at actually learning how it works...

 

[ExploderWizard]

I will second the Citybook series. I have used stuff from those for GURPS,and various editions of D&D. I like how the "stats" are presented as a relative power level of combat and magic use. Even without the NPC's, the locations and maps are worth it alone.

 

[Inferno!]

Nobody's mentioned Pirate's Guide to Freeport yet? Its systemless with companions books for the system of your choice (if you choose to purchase them).

 

[DocDoom]

GURPS Books are pretty good, although they tend to be very "realistic" - whatever that means when you speak about Magic and Spaceships.

However, their crunch is very easy to convert - 1 Round in GURPS is exactly one second, and modifiers to skills/attributes pretty much scale 1 to one to DnD - GURPS uses 3d6 range instead of d20.

Apart from that, the Books are pretty crunchlight, and really well thought out/ researched. Especially good: Vehicles (if you want to build Vehicles that behave realistically, even though they come from a Steampunk setting or whatever), Time Travel, Illuninati (for playing in a world where Conspiracy theories are true. At least some of them. Fnord.) and basically whatever topic you are interested in. Really, these Books ar A-awesome.

 

[Aus_Snow]

What, no love for The Primal Order, from (a rather young) WotC, pre-D&D?

Well, thought I'd mention it anyhow.

 

[GeorgeFields]

A lot of the Kingdoms of Kalamar stuff is excellent setting fluff with very little crunchwise. I use them as constant inspiration for my games, no matter what the setting.

All the Magical Medieval stuff my XRP is great too, a great series that apply no matter what the system (ok, maybe fantasy only!)

I also steal a lot of stuff out of The Book of the Righteous for other fantasy games as well. My last Burning Wheel game had several of the churches prominently featured.

I'll second both Kalamar and Book of the Righteous. Although both contain crunch, the fluff far outweigh it. I'm considering using BotR as the religion for a homebrew setting.

 

[CleverNickName]

I don't play GURPS, I don't know how to play GURPS, and I've never once even read the GURPS Basic Rules.

But I've got a bookshelf full of the sourcebooks. Money better spent than many of the books I've purchased for games I actually play.

Same here...I've got a small collection that I use a lot for world-building. When I was putting together my Egypt-themed campaign, I used the GURPS: Egypt book a *lot* for the setting...it had all of the fluff that I needed to flesh out the culture.