DMs, What Are Your Top 3 Favorite Non-Core Books?

[Garmorn]

Pisonic Handbook w/modes and expansions from Mont's web site.
The Path series books from FFG
Moongoes' The Ultimate series books.

 

[lord irial]

For D&D: Kingdoms of Kalamar CS
Savage Species
Psionics Handbook

For Other d20: Mutants and Masterminds
Traveller T20
Swashbuckling Adventures

 

[Severion]

Chaos Magic; Mongoos publishing
MoP
Everything Poly

 

[Bulak]

1) Forgotten Realms Campaign Setting
2) Manual of the Planes
3) Several monster books (GRR's Books of Fiends, Monsters of Faerûn, MMII)

 

[CRGreathouse]

1. Book of Eldritch Might III: The Nexus
2. Book of Eldritch Might II: Songs and Souls of Power
3. Manual of the Planes

 

[Storminator]

I use FRCS all the time, but that's because I have an FR game.

Beyond Monks certainly tops my list.
HoHF: Elves is about to get an explosion of use in a multitude of games, just because it has so much to offer.
Really cool, but as of yet unused, Touched by the Gods

PS

 

[blackshirt5]

Monster's Handbook
Tome of Horrors
Anything from the Quintesential Line

 

[rounser]

FRCS
Magic of Faerun
Monster Manual II

 

[VorpalBunny]

The FRCS
Races of Faerûn
Oriental Adventures

 

[Flexor the Mighty!]

Manual of the Planes
Tome of Horrors
Legions of Hell