Sonic the Hedgehog

“I'm Sonic, Sonic the Hedgehog!”

―Sonic's Catchphrase

Sonic the Hedgehog is the protagonist of the eponymous video game series, and has served as Sega's company mascot since the release of his first game in 1991. Sonic's sidekick and best friend is named Miles "Tails" Prower, who is a two tailed fox. His first rival is Knuckles the Echidna. He has a troublesome self-proclaimed girlfriend named Amy Rose, who is trying to have a date with him despite his lack of interest. His arch nemesis is called Dr. Ivo Robotnik, who now goes by the name Dr. Eggman (or simply Eggman) which was once a nickname given to him by the Blue Blur himself, until he adopted it.

In The Simpsons

1995: In Marge Be Not Proud (S7E11), he is one of Bart's video game constrictions.
2007: A parody of Sonic the Hedgehog appears in the Enter the Cheatrix episode of The Simpsons Game. He was voiced by Dan Castellaneta.
2008: In That '90s Show (S19E11) the 90's Homer Simpson shows the 90's Marge a sign which depicts Sonic presenting one of the series' trademark Rings to Amy Rose, Sonic's "would-be" love interest in their respective series. This is based on The Adventures of Sonic The Hedgehog TV show when at the end of every episode there would be a segment called "Sonic Says". Notably, Amy's design is the modern one introduced in Sonic Adventure (1998), which is inconsistent with the episode's time-frame (which would be in the early 1990s); possibly, Amy's own appearance could be a contradiction, as she was introduced to the game series in 1993's Sonic CD, and does not appear in the Adventures of Sonic the Hedgehog TV show.
2011: In The Food Wife (S23E5) you can see a parody of Sonic in the video game convention, E4.