Electric Light Orchestra
Break-Up: In the summer of 1986, the group (now reduced to a trio) toured in support of their new disc Balance of Power, and then called it a day. Members of the group carried on in ELO Part II, but the group's leader Jeff Lynne was done. (Even later, The Orchestra rose from the ashes of ELO Part II, but they were an offshoot of an offshoot and barely worth mentioning.)
Reunion: Lynne always saw himself as the Trent Reznor of ELO, and when he reformed the group in 2000 for the new album Zoom he didn't invite any of the original guys back – though keyboardist Richard Tandy did wind up playing on one song. For some reason, Lynne was under the impression the group could still fill arenas and a massive tour was announced.
Duration: One album and one TV concert. This was like one of those 1950s rockets that crashed a few moments after takeoff. The group did a single show for PBS, but the tour sold horribly and the entire thing was called off before it even started. Lynne's done a pretty good job of staying out of the spotlight ever since, though he remains a busy producer.