Please correct me if I'm wrong! (Forumesque 11 is open, also twitter) but I believe MH himself is at the keyboard for the last two strains of Scott Joplin's "Solace," as heard on the soundtrack to the hit movie The Sting.
UPDATE: on Twitter, Ted Gioia confirms that Hamlisch is indeed the pianist. However, Hamlisch's contribution to this soundtrack remains a topic of debate, with some regarding it as a collaborative effort: names also in consideration are Gunther Schuller and Joshua Rifkin, not to mention director George Roy Hill, who apparently wanted Joplin music.
Even if Hamlisch isn't playing (update: he is), it must of taken a dedicated professional to go though all of Scott Joplin in order to find two of the most moving melancholy strains ever written for solo keyboard. The first two strains of Joplin's "Solace," are good, too, but after The Sting -- and the magnificent rubato interpretation by the pianist on the soundtrack -- they were rendered almost irrelevant.
Hamlisch wrote a lot of original music, too, of course. Some of it was wonderfully memorable, some of it was horrible dreck. But surely I'm not the only jazz pianist that owes something to the 70's ragtime revivial, especially The Sting.
Vince Giordano once told me a great story. Wally Rose was a talented ragtime pianist who devoted himself to Joplin long before Joplin signed to a major label. After 1973, when Rose worked in restaurants, patrons would come up to him and say, "Play The Sting! Play The Sting!"
For a while, Rose, Joplin expert that he was, Rose would carefully say, "Oh! You mean, 'Play The Entertainer,' the rag by the great Scott Joplin."
After a few hundred incorrect requests, Rose finally gave up. In response to the injunction, "Play the Sting," Rose would collapse on to the keyboard, his body sounding a dissonant cluster covering several octaves. Then he would bellow, "DEATH! WHERE IS THY STING!"
Update: I just talked to Vince. I got the punchline wrong! Wally Rose, improvisor that he was, made it even funnier with a new gloss on the old phrase: "STING, WHERE IS THY DEATH???! !"