Extra characters:
At the character select screen, press L1 while selecting the following fighters:

Kyo Kusanagi		Kyo Kusanagi version '95
Terry Bogard		Terry Bogard version Real Bout 2 
Andy Bogard		Andy Bogard version Real Bout 2
Joe Higashi		Joe Higashi version '94
Ryo Sakasaki		Ryo Sakasaki version '94
Robert Garcia		Robert Garcia version '94
Yuri Sakazaki		Yuri Sakasaki version '94
Mai Shiranui		Mai Shiranui version Real Bout 2
Yashiro Nanakase	Evil Yashiro Nanakase
Shermie			Evil Shermie
Cris			Evil Cris
Billy Kane		Billy Kane version Real Bout 2
Rugal Bernstein		Evil Rugal Bernstein 

Thanks to Revolution readers Guilherme Henrique, Ernest, Nicholas Toon, Meister Dan, Wolfpac Cyrus, Thiago Malvão Bernardino, Alex Hisao Shigematsu, chris, Jefferson Pimenta, and Bad Boy Badrul!