| Nintendo GBA cart. |  Medal of Honor Advance Model AGB-BMHJ-JPN | 2003 | EA Games Electronic Arts, Inc. |
| Medal game (video) |  Medal Train | 2003 | Andamiro Co., Ltd. |
| Medal game (video) | Medal Train 2 | 2003 | Andamiro Co., Ltd. |
| Medal game (video) | Medal Train 3 | 2003 | Andamiro Co., Ltd. |
| Nintendo GBA cart. | Medarot Ni Core - Kabuto Version Model AGB-A5KJ-JPN | 2003 | Natsume, Inc. Japan |
| Nintendo GBA cart. | Medarot Ni Core - Kuwagata Version Model AGB-A5QJ-JPN | 2003 | Natsume, Inc. Japan |
| PC/MS-Windows CD | Medieval - Total War - Viking Invasion | 2003 | Activision Publishing, Inc. Los Angeles, CA, USA 47875 |
| Slot Machine | Mega Bingo | 2003 | IGS Co., Ltd. International Game System |
| Slot Machine | Mega Bingo II | 2003 | IGS Co., Ltd. International Game System |
| Slot Machine | Mega Bingo III | 2003 | IGS Co., Ltd. International Game System |
| Sony PlayStation 2 disc |  Mega Hits!: Shin Sangoku Musou 2 Model SLPM-66505 | 2003 | KOEI Co., Ltd. Japan |
| Nintendo GBA cart. | Mega Man & Bass Model AGB-A6ME-USA | 2003 | Capcom USA, Inc. Santa Clara, CA, USA 13388 |
| Nintendo GBA cart. | Mega Man & Bass Model AGB-A6MP-EUR | 2003 | Capcom Eurosoft Ltd. London, England 055060 |
| Nintendo GBA cart. | Mega Man Battle Network 3 Blue Model AGB-A3XE-USA | 2003 | Capcom USA, Inc. Santa Clara, CA, USA 13388 |
| Nintendo GBA cart. | Mega Man Battle Network 3 Blue Model AGB-A3XP-EUR | 2003 | Capcom Eurosoft Ltd. London, England 055060 |
| Nintendo GBA cart. | Mega Man Battle Network 3 White Model AGB-A6BE-USA | 2003 | Capcom USA, Inc. Santa Clara, CA, USA 13388 |
| Nintendo GBA cart. | Mega Man Battle Network 3 White Model AGB-A6BP-EUR | 2003 | Capcom Eurosoft Ltd. London, England 055060 |
| Nintendo GBA cart. |  Mega Man Mania | 2003 | Capcom Co., Ltd. Japan |
| Nintendo GameCube disc | Mega Man Network Transmission Model DOL-GREE-USA | 2003 | Capcom Ent., Inc. USA 13388 |
| PC/MS-Windows CD | Mega Man X7 | 2003 | Capcom Ent., Inc. USA 13388 |
| Nintendo GBA cart. | Mega Man Zero 2 Model AGB-A62E-USA | 2003 | Capcom USA, Inc. Santa Clara, CA, USA 13388 |
| Nintendo GBA cart. | Mega Man Zero 2 Model AGB-A62P | 2003 | Capcom Co., Ltd. Japan |
| Slot Machine | Mega Mart | 2003 | GTech Corp. Providence, RI, USA |
| Pachislot | Mega Max | 2003 | Yamasa Japan |
| Pachinko | Megaton Saurer Model GV | 2003 | Maruhon Japan |
| Pachinko | Megaton Saurer Model G | 2003 | Maruhon Japan |
| Arcade Video game | Megatouch 2003.5 | 2003 | Merit Industries, Inc. Bensalem, PA, USA |
| Arcade Video game | Megatouch Force 2003 | 2003 | Merit Industries, Inc. Bensalem, PA, USA |
| Arcade Video game | Megatouch Maxx Ruby 2 | 2003 | Merit Industries, Inc. Bensalem, PA, USA |
| Arcade Video game | Megatouch Maxx Ruby Edition | 2003 | Merit Industries, Inc. Bensalem, PA, USA |
| Nintendo GBA cart. | Meitantei Conan - Nerawareta Tantei Model AGB-AC4J-JPN | 2003 | Banpresto Japan |
| Sony PlayStation CD |  Meitantei Conan - Trick Trick Vol. 0 - Meikyuu no Crossroad Special Disc Model SLPM-80640 | 2003 | Bandai Co., Ltd. Japan |
| Sony PlayStation CD | Meitantei Conan - Trick Trick Vol.1 Model SLPS-03548 | 2003 | Bandai Co., Ltd. Japan |
| Pachinko | MeMeMe | 2003 | Takao Co., Ltd. Japan |
| Sega Dreamcast GD | Memories Off 2nd Model T-19707M-1 | 2003 | KID Kindle Imagine Develop |
| Pachislot | Mephisto | 2003 | Yamasa Japan |
| PC/MS-Windows CD | Mercedes-Benz World Racing | 2003 | TDK Mediactive, Inc. |
| Nintendo GBA cart. | Mermaid Melody - Pichi Pichi Pitch - Pichi Pichi Party Model AGB-BM8J-JPN(RK343-J1) | 2003 | Konami Corp. Japan |
| Nintendo GBA cart. | Mermaid Melody - Pichi Pichi Pitch Model AGB-BMAJ-JPN(RK335-J1) | 2003 | Konami Corp. Japan |
| Slot Machine | Merry Christmas | 2003 | Subsino Co., Ltd. |
