Classic (Niche) Competitors

There have been many throughout the years vying to dominate the video game market. Portable, home consoles, gimmicks, you name it. Which of all Nintendo’s past niche competitor platforms were you most fond of? By niche we’re implying anything non Sega, Sony, and/or Microsoft.

Turbo Duo, 3DO, Game.com, Atari Jaguar etc.?