Lindsey is the only character besides Angel himself to appear in both the first and last episodes of Angel.

Christian Kane originally auditioned for the role of Riley Finn on Buffy the Vampire Slayer.

In "You're Welcome," Lindsey calls Angel a corporate puppet. Two episodes later, Angel does literally become a puppet in the episode "Smile Time."

Christian Kane lends his real singing voice to the episode "Dead End," causing a humorous and seemingly jealous reaction by Angel in Caritas.

Though Christian Kane is a guitar player as well as a singer, it is his KANE band mate Steve Carlson that lends his hands for the performance shots during the Caritas scene in "Dead End."

The fleur-de-lis bracelet that Lindsey wears throughout his time on the show is actually a bracelet that Christian Kane wears to remind him of his mother who is from New Orleans.

Unlike other Buffyverse characters like Angel, Spike, Willow, Andrew, Faith etc., Lindsey never got to seek his redemption. Precognitive Lorne indicates that he never would have, and would never have been part of "the solution".