"Andy" is short for "Andrew," which is derived from the Greek work "Andreas," meaning "man." Although "Andy" is only the 217th most popular name in the US(Wikipedia), several well known people share this name, including actor Andy Garcia(Smokin' Aces and Ocean's Twelve), tennis player Andy Roddick, and Hong Kong celebrity Andy Lau.
"Jennifer" is popular. In fact, it was the most common name given to baby girls in the US between 1970 and 1984(Wikipedia). But did you know it is actually Cornish for "while phantom?" Variations include "Jen," "Jenny," and "Gwen." Popular personalities include actress Jennifer Aniston(best know for being Brad Pitt's ex-wife) and singer Jennifer Lopez.