Well I started off with an Amstrad CPC 464 with a green screen monitor in the mid 80' s before finally getting an MP2 modulator which ensbled me to connect it to a tv to get colour. Wow colour, what an experience. Currently I' ve got nearer 1000 titles on the following formats.

Sega Megadrive - Switched
After being blown away by Altered Beast (yes but it was good at the time, honest) I knew I needed this. So in 1990 I got one with excellent titles like Truxton (Tatsujin), Sonic (eventually), Strider, Revenge of Shinobi (Super Shinobi).
Sega Mega CD 2
1993 and titles like Silpheed, Sonic CD, Final Fight, Thunderhawk and Robo Aleste meant it was time to add.
Sega Nomad
Kicks the GBA in the balls!
Sega Master System 2
Sega Master System to MD adaptor
Sega Saturn - Black US version
Sega Saturn - White Flash Saturn
Sega Dreamcast - Jap
Sega Dreamcast - UK

Nintendo NES
Super Nintendo - Switched
Nintendo 64 - US
Game Cube - Jap Switched
Original Gameboy
Pocket Gameboy
Colour Gameboy

Neo Geo AES
Got it on sale back in 94' what a winner of a machine.
Neo Geo 4 Slot MVS
Neo Geo 1 Slot MVS
Neo 50" Arcade Machine
My pride and joy, now with consoles connected!
Neo Geo Pocket
If only for Metal Slug, Sonic and Card Fighters.

Turbo Duo CD - Jap
PC Engine
Final Soldier, what a winner. A great little system
GT Handheld

Playstation
Playstation 2 - Chipped

XBox - Chipped

Oh and 4000 Mame X roms running, which is quality!