What better way to add something different (and very Seattle) to your reception than an espresso cart? They are incredibly reasonably priced, especially considering most venues charge more for coffee and tea service anyway. The cool thing is that you can create a custom espresso drink (either with or sans alcohol), have them "paint" your monogram in the foam of each drink, and give your guest a really fun treat.
(a delicious cappuccino I had on our last trip to the Netherlands)
Think about having hot chocolate and apple cider as well for that perfect fall touch.
Espresso Elegance in Seattle offers pricing starting at $225 - http://www.espressoelegance.com/