Derek Sherinian has been very active. When he was still in Dream Theater, he was working on a solo project called Planet X. This solo project gave life to his new band, also called Planet X.
Planet X released four albums from 2000 til 2007: Unverse, Live from Oz, MoonBabies and Quantom.
Derek also has released 7 solo albums: Planet X, Inertia, Black Utopia, Mythology, Blood of the Snake, Molecular Heinosity and Oceana.
There was also a period where Derek was playing with Glenn Hughes, Jason Bonham and Joe Bonamassa in a band called Black Country Communion, which released three albums (Self-titled 1, self-titled 2 and Afterglow).
Derek has also guested on many many albums over the years. He’s a session musician for hire, and many bands use him for a solo and whatnot. He’s also supported many artists on the road, such as Billy Idol, Yngwie Malmsteen and more.
Derek Sherinian (along with Charlie Dominic) reunited with Dream Theater in 2004 for the “When Dream And Day Reunite” show. Derek played keyboards on “Metropolis”
A selected portion of his discography can be found here: