Two gifts that my inlaws have enjoyed were...the children made them those fleece blankets where you tie the knots. Each child chose a fleece pattern that they thought 'fit' grandma and grandpa, and we put them together. They were wild, bright blankets, and not color coordinated in the least, but they were a hit. Now they use *only* those blankets for their nightly TV viewing. A little more personal than a snuggie.
Second, last year, I took the kids (I have 2) and we made hand painted ice cream bowls for them. One says 'grandpa's ice cream' and the other 'grandma's' then my son decorated one bowl, daughter the other in colors and designs they thought were fun. My in laws eat ice cream at 9pm every night, so those were a hit, too.
Of course, I'm checking out the thread, because I'm stuck for this year. Already done the mugs, mousepads, calendars, books with photos...