Like most Beatles songs, Being for the Benefit of Mr. Kite! has been covered many times in many different ways. It's a difficult song to cover, I would say, just because it's just so unusual and individual.
First up, Is this alternate version by the Beatles themselves with some interesting differences (vs. the version that made it onto Sgt. Pepper:
Next up, Eddie Izzard performed a particularly memorable version in the movie Across the Universe:
Another version that has just been released is by Minnesota band Van Stee. Their version is part of the Minnesota Beatles Project and proceeds support music education programs in Minnesota public schools. It's worth buying the whole album - there's some great stuff on there.
Finally, one of my favourite versions is by the reggae band Easy Star All Stars, a reggae collective who have recorded a reggae cover version of the entire Sgt. Pepper's album and named it Easy Star's Lonely Hearts Dub Band. They previously gave the same treatment to Pink Floyd's Dark Side of the Moon (Dub side of the Moon) and Radiohead's OK Computer (Radiodread) which are both phenomenally good. I understand that their next release will be a reggae cover of Michael Jackon's Thriller, which should be equally entertaining.