I just heard about an "Iron Composer" competition, which sounds like an interesting exercise in speed writing. Here is how it works:
The first "round" is a resume and sample piece round, which happens between July and September. The final round, held on September 7 in Cleveland, is kind of like the Iron Chef cooking competition: a secret musical ingredient is given to the five composers who are chosen to participate. They are given this "ingredient" at 9:00 in the morning, and have five hours to produce a piece, complete with score and parts. Each composer gets the use of a piano, a computer with Finale or Sibelius, and a printer, and they have to finish their piece by 2:30. The composers lose points if they need to take extra time to finish. Each composer gets 30 minutes to rehearse his or her piece piece, and at 8:00 that night everything is performed in a concert that will be broadcast on WCLV FM radio and simulcast on line. Three judges will judge the pieces based on the use of the secret ingredient, originality, technical command, and overall presentation.
The Prix de Rome music competition began in 1803 and was held every year until 1968. From what I know about Lili Boulanger's experience, composers had four weeks to write a piece or a series of pieces, and they had to adhere to strict guidelines. I don't recall any mention of composers having access to a piano during the composition period (but I guess Boulanger had such a great ear that she wouldn't have needed one anyway).
Speed composing is not my idea of fun (but neither is speed cooking). I imagine that there are people who would love to enter this, just for the sport of it. I wonder what a musical "secret ingredient" might be. An unusual instrument? A tone row? A text to set? A theme to make variations on? An unusual meter? An unusual mode? An electronic tape?