Last but not least: How to surprise your co-workers!
Make a little cardboard oven out of a shoebox (there are tutorials online, but I thought it was way simpler to just wing it... the oven door is made of a page protector, in case you're wondering).
It's fun if the oven door can actually open and close!
Inside the oven, put a picture of the expectant parents, along with a Date Due slip (which is especially perfect if you work at a library).
Order a bunch of morning buns from the local bakery. Pick them up early in the morning, and get to work before anyone else. Set up the oven and the buns in the lounge...