One of my favorite newspaper cartoons that I read almost daily is Calvin and Hobbes by Bill Watterson. It's been in syndication since 1985.
The strip follows the richly imaginative adventures of a little boy named Calvin and his trusty tiger, Hobbes. The tiger is actually a stuffed toy belonging to Calvin. Whether a poignant look at serious family issues or a round of time-travel (with the aid of a well-labeled cardboard box) the two have many adventures together. I know it always brightens my day to remember how much fun it was to be a kid. C&H is a real delight to read.