For the last three or more years at work we have picked names to be someone's secret buddy at work the week before Valentine's Day. For five days we sneak around (my favorite part) and leave things for each other. Some people make other people lunches, or we just leave cute little things in each other's mailboxes.
My buddy left me really neat things everyday and one day left this whole package of card making things. It sure put a big smile on my face! (and it covered the report card piles on my desk!)