Warning : If you don't like Dream Theater or it's musician's side projects, ignore this post.
Lately I've been getting into Dream Theater side projects/solo albums alot. Like OSI, original keyboardist Kevin Moore's band. It's some mainly keyboard-centric stuff, but it's really mesmerizing, just like the keyboard melodies he used to make while with DT. If I'm not mistaken, he also sings in this band as well.
(Except this song, it's Mikeal Akerfeldt)
Then there's James LaBrie's solo work. This may not be for everyone. There are definitely some Nu-Metal vibes going on on his first album, and some horridly placed metalcore screams on the second one, but I still like them. (Note, these are actually his third and fourth solo albums. The first two were under the name Mullmuzzler. Haven't heard any of that yet.)
And finally, Liquid Tension Experiment. It's basically Dream Theater, without a singer and a different bassist. Completely instrumental. The mood switches from Dream Theater sounding music on most songs, broken up by some really strange shorter songs. The last song from their first album "Three Minute Warning" is a 28 minute jam session that's kinda hard to digest. The other songs make up for it though.
[ame]http://www.youtube.com/watch?v=RTQm7Yag_JY&feature=related[/ame]
[ame]http://www.youtube.com/watch?v=4MC99Try0qI&feature=related[/ame]