Anachronox. It came out in 2001, but was based on 1997 Quake 2 tech, so... quasi-classic. Ish. - Edit 1
Before modification by Zalis at 19/01/2010 03:46:41 PM
Under-appreciated, at least, if not classic by definition. It had its issues, and ended up releasing a bit truncated, but I'd still recommend it to anyone who can appreciate a quirky RPG.