Now that I'm playing in a couple cover bands, I notice a song that's often covered is "The Weight."
The Weight, as played by The Band, http://youtu.be/sjCw3-YTffo has a 3/4 bar in the middle of the chorus. Start counting with "Take a load off..."
And... and... and.. you put the load, put the load, right on me...
It's amazing how hard it can be to get it right! Some bands do:

• Weezer
• Panic at the Disco
• John Fogerty & The Black Keys
• Gillian Welch & Old Crow Medicine Show
• Elton John (with Zack Brown, Mumford and Sons, Mavis Staples and others on the 55th Grammy Awards)
• and one of my favorites: Jimmy Fallon & the Muppets

Sadly, many didn't. These put a 2/4 bar instead (oh my) and it just makes a mess:

• Bruce Springsteen
• Jimmy Page, The Edge, Jack White (It might get loud)
• Wilco, Nick Lowe & Mavis Staples
• Waylon Jennings (despite the cool horn section it just seems sloppy)

Others put a 4/4 bar instead, extending the "and... and... and...", most notably, The ACL/Americana Awards All Star Cast tribute to Levon Helm, and Aretha Franklin. Aretha Franklin's version is more of a funky tribute to The Weight than a real cover. She kinda totally skips over that whole part of the chorus, and the awesome funk groove and horn section more than makes up for it.

In his later years, for his "midnight rambles" even Levon would play straight through in 4/4 if there was a large group singing with him. So who knows...