Honestly you can't go wrong with anything from Starbucks. The mug sets this year are awesome, you can also just pick up a gift card...there is nothing wrong with a gift card to a coffee shop. Nothing.
So appropriate for this area, everyone assumes the other works for some secret agency when they do not disclose who they work for. I mean why not?
Perfect for the coffee or tea snob in the office. Plus it is perfect to keep at your desk if walking around searching for coffee is not your thing.
What are you exchanging this year?