They electrified audiences with their singing and dancing in the 1978 musical "Grease" and now they're back. John Travolta and Olivia Newton-John, "Danny and Sandy" themselves, are back with a new Christmas charity  album called "This Christmas". A video for the single "I Think You Might Like It" has been released and while the dancing may not be up to "Grease" standards we think you'll find it fun. Check it out along with a classic performance from "Grease".