Matt Damon has bared his butt as part of a prank on U.S. TV personality Jimmy Kimmel. The movie star tweeted a photo of a fax of his bare buttocks to Kimmel and longtime pal Ben Affleck after they poked fun at his lack of Twitter presence. He accompanied the picture with the caption: "Dear Ben & Jimmy, Here's my fax. Love, MD. Faxtag: KimmelHasManBoobs." The comedian posted the image on his own Twitter.com page on Friday (14Feb14), adding, "@BenAffleck - did you see what your 'friend' Matt faxed to us?" prompting Affleck to write, "Looks like u from here, Jimmy." Kimmel has made Damon the butt of his jokes on his late-night show for years and earlier this month (Feb14) he ignored the Bourne Identity star during an interview with the cast of The Monuments Men. Damon famously took over Kimmel's show in January, 2013 and tied the host to a chair as he conducted interviews with all-star guests like Demi Moore, Gary Oldman and Nicole Kidman, who all took aim at the comic as he sat behind them. The latest 'tiff' began last week when Affleck took to Twitter to thank Kimmel for retweeting a link promoting his "win a date with..." charity contest, benefitting the Eastern Congo Initiative and Damon's favourite cause Water.org. Affleck wrote, "I thank you buddy. And @easterncongo & @water thank you. Matt on the other hand? Matt you there? Right. We will fax you." Kimmel responded by joking, "Matt is probably too scared to get on twitter because no one likes him."