The Flaming Lips - Yoshimi Battles The Pink Robots (2002)
They had an incredible decade prior to this releasing 3 other top notch albums, but by far this one sticks out as the most successful and easiest to pickup. They have a lot more after this release as well, but I think Wayne found himself diving into an era of depression and it absolutely showed on those later releases. The last release was good but also nothing special at the same time.