| Type | Game | Year | Publisher |
|---|
|
| Arcade Video game | Omega Fighter [Model UPL-89016] | 1989 | UPL Co., Ltd. [Universal PlayLand] |
|
| Commodore VIC-20 cart. | Omega Race | 1982 | Commodore, Ltd. |
|
| NEC PC-8001 type-in | Omotesandou Adventure #1 | 1982 | ASCII Corp. [Japan] |
|
| Sharp MZ-80K type-in | Omotesandou Adventure #1 | 1982 | ASCII Corp. [Japan] |
|
| BASIC soft. type-in | One Check | 1978 | Workman Publishing [NY, USA] |
|
| Coin-op Misc. game | One World | 1947 | Amusement Enterprises, Inc. [New York, NY, USA] |
|
| IBM PC/AT DOS 3.5in. disk | Onesimus - A Quest for Freedom | 1992 | Ark Multimedia Publishing |
|
| Arcade Video game | Onna Sansirou - Typhoon Gal | 1985 | Taito Corp. [Japan] |
|
| Arcade Video game | Oo-edo Fight | 1994 | Kaneko Co., Ltd. [Tokyo, Japan] |
|
| Arcade Video game | OOPArts | 1992 | SEGA Enterprises, Ltd. [Tokyo, Japan] |
|
| Arcade Video game | OOPS | 1978 | Vectorbeam [Union City, CA, USA] |
|
| Fujitsu FM-7 cass. | Oozumou [Model FUCP-13032] | 1983 | Champion Soft. [Japan] |
|
| DEC PDP-5 soft. | OPAK [No. 5-2.1] | 1965 | DECUS [Digital Equipment Computer Users' Society] |
|
| IBM PC/AT DOS 3.5in. disk | Operation Crusader | 1994 | Avalon Hill Video Game Co., The [Baltimore, MD, USA] |
|
| SNK Neo-Geo MVS cart. | Operation Ragnarok | 1994 | NMK |
|
| Atari Falcon 030 disk | Operation SKUUM | 1996 | Logitron |
|
| Arcade Video game | Operation Thunder Hurricane | 1997 | Konami Co., Ltd. [Japan] |
|
| Pinball | Operation Thunder [Model 732] | 1992 | Premier Technology Co. [Bensenville, IL, USA] |
|
| Arcade Video game | Operation Thunderbolt | 1988 | Taito Corp. [Japan] |
|
| Arcade Video game | Operation Wolf | 1987 | Taito Corp. [Japan] |
|
| Arcade Video game | Operation Wolf 3 | 1994 | Taito Corp. [Japan] |
|
| TRS-80 type-in | Operation: Sabotage | 1982 | SoftSide Publications, Inc. |
|
| Apple II type-in | Operation: Sabotage | 1982 | SoftSide Publications, Inc. |
|
| Atari 400/800 type-in | Operation: Sabotage | 1982 | SoftSide Publications, Inc. |
|
| IBM PC type-in | Operation: Sabotage | 1982 | SoftSide Publications, Inc. |
|
| PC/MS-Windows CD | Operation: Weather Disaster | 1995 | Discovery Channel Multimedia |
|
| Dick Smith Super-80 cass. | Opposites [Model 064L4] | 198? | Unknown |
|
| BASIC soft. type-in | Orbit | 1978 | Workman Publishing [NY, USA] |
|
| Pinball | Orbit [Model 321] | 1972 | Gottlieb & Co., D. [Chicago, IL, USA] |
|
| Arcade Video game | Orbs | 1994 | American Sammy Corp. [Torrance, CA, USA] |
|
| Sony PlayStation CD-ROM | Ore! Tomba [Model SLPS-01144] | 1997 | Whoopee Camp |
|
| Apple II cass. | Oregon | 1978 | Apple Pugetsound Program Library Exchange |
|
| Commodore C64 cass. | Organism | 2018 | Psytronik Soft. |
|
| IGS PGM cart. | Oriental Legend | 1997 | IGS Co., Ltd. [International Game System] |
|
| PLATO soft. | Orthanc | 1975 | Resch & Kemp & Hagstrom |
|
| RCA COSMAC VIP type-in | Ortho | 1980 | Association of Computer Experimenters |
|
| Nintendo Game Boy Cart. | Osawagase! Penguin Boy [Model DMG-PNJ] | 1990 | Natsume, Inc. [Japan] |
|
| DEC PDP-5 soft. | Oscilloscope Symbol Generator [No. 5-23] | 1965 | DECUS [Digital Equipment Computer Users' Society] |
|
| Arcade Video game | Oshaberi Macha Monoshiri Quiz | 1983 | Logitec Co., Ltd. |
|
| SNK Neo-Geo CD | Oshidashi Zintrick [Model ADCD-104] | 1996 | SNK Corp. [Shin Nihon Kikaku] [Japan] |
|
| Nintendo Super Famicom cart. | Osu!! Karate-bu [Model SHVC-OJ] | 1994 | Culture Brain |
|
| Bally Astrocade cass. | Othello | 1980 | Cursor Group, The |
|
| Bally Astrocade cass. | Othello | 198? | Perkins & Brigden |
|
| Arcade Video game | Otomedius | 2007 | Konami Digital Ent. Co., Ltd. |
