Morse has been a guest musician on several 2005 albums, including Ajalon's "Threshold of Eternity", Roine Stolt's "Wallstreet Voodoo", Salem Hill's "Mimi's Magic Moment", and Mark Leniger's "Walk on Water". Morse was one of several musical guests to appear on Dream Theater's 2007 album "Systematic Chaos", on the song "Repentance". These guests were recorded apologizing to important people in their lives for wrongdoings committed in the past. Morse provided vocals for the first track on Jordan Rudess' tribute album "The Road Home".