| Slot Machine |  Monopoly - Fiery Sevens | 2004 | WMS Gaming, Inc. Chicago, IL, USA |
| Slot Machine | Monopoly - Reel Riches | 2004 | WMS Gaming, Inc. Chicago, IL, USA |
| Slot Machine | Monopoly - Shake Rattle and Roll | 2004 | WMS Gaming, Inc. Chicago, IL, USA |
| Slot Machine | Monopoly - Wild Dice | 2004 | WMS Gaming, Inc. Chicago, IL, USA |
| Nintendo GBA cart. | Monopoly Model AGB-BUME-USA | 2004 | DSI Games |
| Nintendo GBA cart. | Monopoly Model AGB-BUMP | 2004 | Zoo Digital Publishing |
| Microsoft XBOX disc | Monster Garage | 2004 | Unknown |
| Medal game (video) | Monster Gate Online | 2004 | Konami Corp. Japan |
| Slot Machine | Monster Millions | 2004 | IGT International Game Technologies Reno, NV, USA |
| Slot Machine | Monster Party | 2004 | Subsino Co., Ltd. |
| Nintendo GBA cart. | Monster Summoner Model AGB-A3NJ-JPN | 2004 | Ertain |
| Nintendo GBA cart. | Monster Trucks Model AGB-BMCE-USA | 2004 | Majesco Sales, Inc. |
| Nintendo GBA cart. | Monster Trucks Model AGB-BMCP-EUR | 2004 | Majesco Sales, Inc. |
| Nintendo GBA cart. | Monster! Bass Fishing Model AGB-A4BE-USA | 2004 | AIA |
| Slot Machine | Monty Python and the Holy Grail | 2004 | IGT International Game Technologies Reno, NV, USA |
| Slot Machine | Moola Mother Lode | 2004 | IGT International Game Technologies Reno, NV, USA |
| Slot Machine | Moolah Rouge | 2004 | WMS Gaming, Inc. Chicago, IL, USA |
| Video Slot Machine | Moon Fire Jackpot Carnival | 2004 | Aristocrat Leisure Industries Pty, Ltd. |
| Slot Machine | Moonshine | 2004 | IGT International Game Technologies Reno, NV, USA |
| PC/MS-Windows CD | Moorhuhn Kart 2 | 2004 | Ak Tronic Soft. & Services GmbH |
| PC/MS-Windows CD | Moorhuhn Pinball | 2004 | Ak Tronic Soft. & Services GmbH |
| PC/MS-Windows CD | Moorhuhn Wanted | 2004 | Ak Tronic Soft. & Services GmbH |
| Pachislot | Morino Icchan | 2004 | Union Machinery |
| Dedicated Console | Mortal Kombat | 2004 | Jakks Pacific, Inc. |
| Microsoft XBOX disc | Mortal Kombat - Deception | 2004 | Unknown |
| Microsoft XBOX disc | Mortal Kombat - Deception - Premium Pack | 2004 | Unknown |
| Sony PlayStation 2 disc | Mortal Kombat - Deception Model SLES-52705 | 2004 | Midway Home Ent. |
| Slot Machine | Mother Lode | 2004 | IGT International Game Technologies Reno, NV, USA |
| Redemption game (mechanical) | Movie Stop | 2004 | Bay Tek, Inc. Pulaski, WI, USA |
| MSX 2 disk | Mr Hawaii | 2004 | Unknown Japan |
| MSX cart. | Mr. Chef & the Sausages Hb | 2004 | Paxanga Soft |
| Nintendo DS cart. | Mr. Driller - Drill Spirits Model NTR-ADRE-USA | 2004 | NAMCO Hometek, Ltd. USA |
| Nintendo DS cart. | Mr. Driller - Drill Spirits Model NTR-ADRJ-JPN | 2004 | NAMCO, Ltd. Japan |
| Nintendo GBA cart. |  Mr. Driller 2 Model AGB-BR2P | 2004 | NAMCO, Ltd. Japan |
| Nintendo GBA cart. | Mr. Incredible Model AGB-BICJ-JPN | 2004 | D3 Publisher, Inc. |
| Nintendo GameCube disc | Mr. Incredibles | 2004 | D3 Publisher, Inc. |
| Slot Machine | Mr. Payback | 2004 | IGT International Game Technologies Reno, NV, USA |
| PC/MS-Windows CD | Mrs. Jiyanki | 2004 | Blue Gale |
| Slot Machine | Ms. Little Green Men Reel Touch | 2004 | IGT International Game Technologies Reno, NV, USA |
| Microsoft XBOX disc | Ms. Pac-Man | 2004 | Unknown |
