And let me be the first in this thread to say: Steven Wilson.
I've been debating on whether not to get the In The Court of the Crimson King boxset with the 5.1 mix and all the extra goodies. I do like that album, and it is a semi-nostalgic album for me, but I don't know if I like it enough to fork over all the cash for about 7 variations of the same album.
But the PT mixes are absolutely amazing... Lightbulb Sun in particular stands out for me.
We should get our surround sound album collections too... this is what I have at the moment
Porcupine Tree - Stupid Dream (DVD-A)
Porcupine Tree - Lightbulb Sun (DVD-A)
Porcupine Tree - Fear of a Blank Planet (DVD-A)
Porcupine Tree - The Incident (DVD-A)
Elton John - Madman Across the Water (SACD)
Elton John - Goodbye Yellow Brick Road (SACD)
Pink Floyd - Dark Side of the Moon (SACD)
Rush - Snakes and Arrows (DVD-A)
Plus a bunch of fan mixes I've downloaded. Some of them are really good and sound legit enough to be actual releases.