Eminem has all but disappeared from the world but lately he has made some spotted appearances. We previously reported that he called into his Shade45 radio station and pranked LL Cool J [listen here]. Now he is contributing to the music side of things. Em will be contributing to a remix to Masta Ace's classic song "Slaughtahouse." The remix will be featured on the recently released RMXXOLOGY, where em shows off his production skills by lowering the original bass and making it into a march-like beat, according to sohh.com Tone-Loc and The Pharcyde are featured on the mainly west coast album.