I always loved Red Buttons. He was great in movies like "The Longest Day" (" Loud and Clear, sir!" and the Poseidon Adventure, but he was also great on all the TV shows I remember from when I was a kid. He'd be on Johnny Carson, Dean Martin, even Laugh-in. A funny, Funny guy, especially for an old guy. The Times did a nice Obit for him, and it's worth reading.
Sort of like  Days of Summer, except instead of meeting Zooey Deschanel, Joseph Gordon-Levitt meets cancer. Seth Rogen and writer Will Reiser's cancer tragi-comedy hits the funny bone, tugs at the heartstrings, and has it both ways.