A "Who Is BJ Hughes?" t-shirt from Cafe Press.
When Ahmed Best did not return to play Jar Jar Binks in The Clone Wars, B.J. Hughes was chosen to take over. Almost immediately, fans grew upset over the poor quality of Hughes' Jar Jar voice, and began to wonder who this new actor was. Research conducted by numerous parties (most notably Jimmy Mac) produced no information, and to this day, nothing is known about B.J. Hughes other than his role as Jar Jar in The Clone Wars. Some have speculated wildly that "B.J. Hughes" is a pseudonym for Dave Filoni himself.
The mystery of Hughes' identity led to the "Who Is B.J. Hughes?" running joke on The ForceCast.