| | Olympia (Bellfruit) (Dutch) (Scorpion 1) | 1969 | BFM/ELAM | sc1olym | | 0.00 |
| | Olympian Games (Russia) | 2002 | Astro | oligam | | 0.00 |
| | Olympic Games | 1984 | Jeutel | olympic | | 0.00 |
| | Olympic Gold (Bellfruit) (set 1, UK) (Scorpion 2/3) | 1969 | BFM | sc2olgld | | 0.00 |
| | Olympic Gold (Bellfruit) (set 1, UK, Protocol) (Scorpion 2/3) (clone of: sc2olgld) | 1969 | BFM | sc2olgldp | | 0.00 |
| | Olympic Gold (Bellfruit) (set 2, UK, 10GBP Jackpot) (Scorpion 2/3) (clone of: sc2olgld) | 1969 | BFM | sc2olgld1 | | 0.00 |
| | Olympic Gold (Bellfruit) (set 2, UK, 10GBP Jackpot, Protocol) (Scorpion 2/3) (clone of: sc2olgld) | 1969 | BFM | sc2olgld1p | | 0.00 |
| | Olympic Gold (German) (Nova) (MPU4) (set 1) | 1969 | Bwb | m4olygn | | 0.00 |
| | Olympic Gold (German) (Nova) (MPU4) (set 2) (clone of: m4olygn) | 1969 | Bwb | m4olygn__a | | 0.00 |
| | Olympic Hot Stuff (TAS 5 Reel System) | 1969 | Olympic Video Gaming | hotstuff | | 0.00 |
 | Olympic Soccer '92 (set 1) (clone of: cupsoc) | 1992 | Seibu Kaihatsu | olysoc92 | Sports / Soccer | 0.00 |
| Olympic Soccer '92 (set 2) (clone of: cupsoc) | 1992 | Seibu Kaihatsu | olysoc92a | | 0.00 |
| | Olympus | 1986 | Juegos Populares | olympus | | 0.00 |
 | Omega (clone of: theend) | 1969 | bootleg? | omega | Shooter / Gallery | 0.00 |
| | Omega (Barcrest) (Dutch) (MPU4) | 1969 | Barcrest | m4omega | | 0.00 |
| | Omega (Maygay) (M1A/B) | 1969 | Maygay | m1omega | | 0.00 |
 | Omega Fighter | 1989 | UPL | omegaf | Shooter / Flying Vertical | 6.60 |
| Omega Fighter Special (clone of: omegaf) | 1989 | UPL | omegafs | Shooter / Flying Vertical | 0.00 |
 | Omega Race (set 1) | 1981 | Midway | omegrace | Shooter / Field | 7.87 |
| Omega Race (set 2) (clone of: omegrace) | 1981 | Midway | omegrace2 | | 0.00 |
