Groups - Demozoo

Osmium Path

Osmium Staff

OSMiUM Staff (.ca/1994)

Osmose

Osmosis

OSS

OST

ost productions

Ostalb Cracking Association - OCA

Ostebulen

Otak Inc.

OtakInc

Otaku Brigade

Otaku United Studio

Other Sight

Otherside

Otinanum

Otomata Labs

OTT-Design

Otto Dix - Ottodix

Ouch

Ouich

our 5oft

Our Own Fucking Network (elite/bbs/network) - OOF, OOF Net, OOFNet

Our Soft

our5oft

Out Of Control

Out of Order (c64) - OOO

Out of Order (atari) - OoO

Out Rage Pirates (PC/Warez) - ORP

Outbreak (pc?/warez)

Outbreak (pc) - OTB

Outcast (pc)

Outcast (c64/.de)

Outdoor

Outer Heaven - oHn

Outer Space

Outer Space Alliance

Outherlimits

Outkazt

Outland Quest Software

Outlanders

Outlaw PDS

Outlaw Triad

Outlaws (amiga/.no)

Outlaws (pc/warez/.de/1995) - OTS

Outlaws (c64/.us)

Outlaws (pc/.fr) - OTL

Outlaws (amiga/pc/warez/bbs/1993+) - OTL, The Outlaws

Outlaws Exchange - OX