JPL will celebrate the 50 years in space with a float in the Rose Parade, January 1, 2008.
"In January 2008 we celebrate the 50th Anniversary of Explorer 1, the first American satellite, which was built at JPL.? This is a historic milestone not only for the Jet Propulsion?Laboratory, Caltech and Pasadena, but for the country," said Charles Elachi, director of?JPL. "I can think of nothing better than kicking off the celebration?with a float in the ultimate New Year's pageant, the Rose Parade." JPL is managed for NASA by the California Institute of Technology in Pasadena.
More at NASA.gov here.
UPDATE 1/6/08: An article about the JPL float here at About Space.com.