After lookíng for some covers on youtube I found, all from 2010 sorting when the date they were put up,
One of the most ambitious and awesome covers I've seen in my entire DT-fan life, a marching band performing parts of IWBY, Vacant and Ouverture 1928, look for yourself, it's amazing! I promise you!:
https://www.youtube.com/watch?v=ehtzbvP6erMSome guys from Asia (AdliB) covering Sacrificed Sons on Split Screen, this almost is in par with the Thiagocampos cover of Metropolis part 1 I think, at least instrumentally, the vocals could have been a bit better but they're affordable, anyway here is it:
https://www.youtube.com/watch?v=_P_RVQCKoCMThis is some other splitscreen cover guys called Threat Jam, who in their first cover performs Another Day, again another top notch performance:
https://www.youtube.com/watch?v=-mz7fJ78_hoAnd finally, a live performance, without a keyboard but with an added guitar instead, which makes it even more metal, cover of Lie:
https://www.youtube.com/watch?v=qhFbJPi8c8g The vocals are maybe not the best but when he tries the higher register it sounds suprisingly good to a song like Lie, the instrumenal part of the cover is good and I really like the the soloing and the part from 5:25 - 5:52.
it's when I watch GOOD and DIFFERENT (like the ambitious marching band ) covers like these above, that my adminiration for Dream Theater, which is already really high goes up even more, because you learn to appriciate the complexity of DT:s music and how rich it is in its variety. Does this apply to you as well?