This is the name of a composition by John Cage. The composition is currently being performed in a church in the city of Halberstadt in Germany.

ASLSP stands for "As Slow As Possible". Originally, John Cage wrote the piece as a 20-minute piece for the piano (then called ASLSP), but it has been extended, oh ever so slightly, to 639 years. The piece began on September 5, 2001, with an 18 month rest note. The first chord (three notes) will be played on January 5, 2003, followed by a short rest until July 5, 2004, when two more notes will be played. This is followed by a rest until 2639, during which tea and cookies will be served.

Oh, and I'm not making this up (except for the bit about tea and cookies).

Michael Betzle, the head of the John Cage Organ Foundation, explained that the long period of performance was meant to form a "contrast to the breathless pace of change in the modern-day world". The period of 639 years was chosen because the first of a series of famous organs in the town was completed 639 years ago.

Organ2/ASLSP is being performed on a brand-new organ built specially for the occasion by organ-maker Gerhard Woehl, in Halberstadt's former Buchardi monastery. Believe it or not, 360 visitors paid 30DM (each) to witness the beginning of the concert. As the concert begins with a rest, this included only inflating the organ's bellows, a terrifically moving event. To quote one person who saw it "it was a terrifically moving event."

Should you wish to listen to this incredible composition, the church is open to visitors every day.