Hightlight for the answers, and happy whatever.
Joel is Dr. McNinja.
Matt is Campy from Furthia High.
Clive is Paul, who is a ghost, from Pictures for Sad Chidren.
Artie is... not a secret, you know who the hell he is.
Dave is Warbot, from Warbot in Accounting.
Zoë is the purple one from Housepets.
Angie is the other one from Housepets.
Kelly is Dilbert, from the neeewwwssspaper.