[Arryn]

Planescape Torment - Black Isle Studios (Interplay)
Fallout - Black Isle Studios (Interplay)
Arcanum - Troika Games (Sierra)
NWN - Bioware (Atari)

Bioware is famous for Baldur's Gate (etc.), which they developed in conjunction with Black Isle (yes, two major design studios on one project). Bioware's most recent product is Knights of the Old Republic, distributed by LucasArts.

Troika's most recent effort is the POS game Temple of Elemental Evil. OTOH, they are working on Vampire: Bloodlines, which may give me cause to forgive them for prostituting themselves with Temple.