The songs that are sung to Lorne by Lindsey in Angel: Dead End (2001), and by one of his clients in Angel: Sleep Tight (2002), were both written by co-creator and executive producer David Greenwalt, as was the title theme to Cordy's sitcom, in the fantasy sequences, in the episode Angel: Birthday (2002). That song was sung by both Greenwalt and consulting producer Marti Noxon, who also appears in the sequence.
Don't you understand that I'm gone?
A goof seen in archive footage from Angel: City of... (1999) that appears in the opening credits of every episode is when Angel is walking down an alley. In a puddle of water you can see his reflection. Though originally a mistake, they choose to take it through the whole show, as a symbol of his soul.
During the first seconds of the opening credits, the red rim of a chalice in the background forms the shape of a halo over the name ANGEL.
The R1 and R2-UK DVDs of season 2 are presented in widescreen (16:9), whereas the television broadcasts were not. They show an open matte image, which shows more on the left and the right side but sometimes even show crewmembers or other things that were not meant to be seen. They 4:3 framing is the one intended to be seen.