Random songs, film and tv themes that are stuck in my head.......

Saved by the Bell, Gremlins, Don't Stop Me Now, Stargate SG1 and Stargate Atlantis, The Friends Theme, Two Pints of Larger Theme, Paint It Black, Doctor Who, U.N.I.T Theme for Doctor Who, All songs from Grease and Grease 2, Scrubs theme, How To Save A Life, We Will Rock You, Skid Row/Downtown from Little Shop of Horrors, Pirates of the Caribbean, Good Vibrations, Summer Holiday, Johnny B. Goode and Hakuna Matata. But i have no idea why they are stuck in my head especially when i've not heard some of them in ages......