Many great ones here but two others that haven't been mentioned that just blow me out of the freakin' water are "Staring at the Sun (Brothers in Rhythm Club Mix)" and Craig Armstrong's take on "Stay (Faraway (So Close!)", perhaps not a true remix so much as an alternate version, but let's not split hairs, eh? I also love almost everything Paul Oakenfold touches of U2's (though, for me, his Perfecto take on "Even Better Than the Real Thing" hasn't aged as well as his others--I much prefer the Apollo 440 ones). In the realm of unofficial remixes, the Johnny Vicious '99 white-label remix of "Where the Streets Have No Name", the fusion of Eminem's "Without Me" with U2's "With or Without You" and Ronald's Mega-Remix (which combines tracks from 1983 through 2001 for over 30 minutes straight) are all unparalleled.