Liquid Tension Experiment sure is fun, but they're more like "hey look at how well i can play guitar/drums/*instrument*" than "this is a well crafted song." They're good listening, not spectacular. Another artist who's pretty experimental I just started listening to is Gas (alias of Wolfgang Voigt.) It is like ambient with a beat. Fun stuff. I friended B!CD, my charts are really funky due to seasonal taste changes. I've listened to a fair few of the bands in your top list... Amon Tobin used to be one of my favourite artists actually, great to throw on in the background in the summer, and Mogwai was one of my faves in high school. And as for an introduction to Xanopticon, I recommend Broken Eye Teeth. The ending is beautiful.