Syd Barrett formed The Pink Floyd Sound (soon dropping the first and last words) with three fellow Cambridge university students, bassist Roger Waters, keyboardist Richard Wright, and drummer Nick Mason. After their early singles and debut LP defined British psychedelia, Barrett's acid-fueled mental problems led to his replacement by David Gilmour in 1968. From there, Pink Floyd perfected a dark but beautiful sound over a string of '70s classics, until personality clashes divided the band in the '80s. A one-off reunion at 2005's Live 8 benefit buried the hatchet before Wright's 2008 death.