| | Otenki Kororin (V2.01J) | 2001 | Takumi | otenki | | 6.33 |
| | Othello (version 3.0) | 1984 | Success | othello | | 0.00 |
 | Othello Derby (Japan) | 1995 | Sunwise | othldrby | Tabletop / Othello | 6.50 |
 | Othello Shiyouyo (J 980423 V1.002) | 1998 | Success | othellos | Tabletop / Othello | 0.00 |
 | Otogizoushi Urashima Mahjong (Japan) | 1989 | UPL | urashima | Unplayable | 0.00 |
 | Otona no Mahjong (Japan 880628) | 1988 | Apple | otonano | Tabletop / Mahjong *Mature* | 0.00 |
 | Out Run (bootleg) (clone of: outrun) | 1986 | bootleg | outrunb | Driving / Race (chase view) | 0.00 |
| Out Run (deluxe sitdown) (clone of: outrun) | 1986 | Sega | outrundx | Driving / Race (chase view) | 0.00 |
| | Out Run (Mega-Tech, SMS based) | 1987 | Sega | mt_orun | | 0.00 |
| Out Run (sitdown/upright) (clone of: outrun) | 1986 | Sega | outruno | | 0.00 |
| Out Run (sitdown/upright, Rev A) (clone of: outrun) | 1986 | Sega | outrunra | | 0.00 |
| Out Run (sitdown/upright, Rev B) | 1986 | Sega | outrun | Driving / Race (chase view) | 9.66 |
| | Out Run 2 (Rev A) (GDX-0004A) | 2003 | Sega | outr2 | | 10.00 |
| | Out Run 2 Special Tours (Rev A) (GDX-0014A) | 2004 | Sega | outr2st | | 0.00 |
 | Out Zone (set 1) | 1990 | Toaplan | outzone | Shooter / Walking | 7.30 |
| Out Zone (set 2) (clone of: outzone) | 1990 | Toaplan | outzonea | Shooter / Walking | 0.00 |
| Out Zone (set 3, prototype?) (clone of: outzone) | 1990 | Toaplan | outzoneb | | 0.00 |
| Out Zone (set 4) (clone of: outzone) | 1990 | Toaplan | outzonec | | 0.00 |
| Out Zone (set 5) (clone of: outzone) | 1990 | Toaplan | outzoned | | 0.00 |
 | Outfoxies (Japan, OU1) (clone of: outfxies) | 1994 | Namco | outfxiesj | | 0.00 |
