'Paul Pfeiffer' from The Wonder Years. My fave. Paul was a good best friend / neighbor and Kevin wasn't that nice to Paul. Everyone else liked Paul. Paul would say all sorts of amazing things, like, upon receiving a B on a paper, he said: "a B is like kissing your sister."
'Skippy' from Family Ties. I liked Skippy's dynamic with each member of the Keaton family and also with Nick. It was always a mystery whether or not any of the Keatons actually liked Skippy.
'Sam' from Clarissa Explains it All. I idolized Clarissa so the fact that her best friend was a dude that would climb a ladder into her room amazed me.
Okay, not even sure why I am including Kimmy Gibbler because she is awful in all ways and I dreaded when she would appear on an episode of Full House and ruin it all for me, but she's such a neighbor. And I like her blue cheetah print tube dresses.
'Brian Krakow' from My So Called Life. I hate Brian but he is such a solid character. Always riding around Angela's house on a tiny bicycle or reading a book in a tree. A real creeper.
'Peter' from The Cosby Show. Peter is genius. His silence and running away is comical magic. I love his grey sweatsuits.
'Six' from Blossom. Only for nostalgic reasons. When the show was on-air I was ten years old and thought that her fast talking antics were what I wanted from a best friend. (Best friends of girls in tv shows are always so effervescent.) She had a skirt made out of ties. In retrospect she was pretty 90's, because it was the 90's, but she did it well.