This is ASTONISHING!
Back row, left to right: Dwight (The Office), Caprica 6 (Battlestar Galactica), Dr. House (House), JD (Scrubs), Tobias (Arrested Development), Liz Lemon (30 Rock), River (Firefly), Jack and Vincent (LOST), The 11th Doctor (Doctor Who), Walter (Breaking Bad), Sheriff (Walking Dead)
Middle row: Buffy (Buffy the Vampire Slayer), Bill (True Blood), Jeff (Community), Quinn or really any other cheerleader from (Glee), Barney (How I Met Your Mother), Don Draper (Mad Men), Dexter (Dexter), Sherlock Holmes (Sherlock)
Bottom row: Sheldon (Big Bang Theory), Spock (Star Trek:TOS), Chuck (Chuck), Sydney Bristow (Alias)
Window: TARDIS (Doctor Who), USS Enterprise (Star Trek), Galactica (Battlestar Galactica), Serenity (Firefly)
Also, the dog is sorta supposed to look like the dog from Frasier, and the cat is sorta like the one from Sabrina the Teenage Witch