I just discovered a very cool idea, courtesy of Gretchen and The Happiness Project. For the last year, she's been keeping a One Sentence Journal for a year now - I am very intrigued, and thinking of doing the same. Consider this, from her post:
"Each night, I write one sentence (well, actually, usually it's three or four sentences, but by calling it a "one sentence journal" I keep my expectations realistic) about what happened that day to me, the Big Man, and the girls.
Right now, I can't imagine forgetting the time when the Little Girl said politely, "Can I have some more pajamas on my pasta?" when she meant "parmesan," but I will, I will."
Don't know about you, but I think that's pretty cool. She also has plans to create bound books of the sentences for her girls and her husband. Check out the details in her post.