My husband and I wanted to announce our pregnancy in a creative way. We rented a tandem bike, bought a used tricycle off Craigslist, and went to a local park. The most difficult (and slightly humorous) part about the whole thing was the tandem bike was too tall for both of us, and we had our camera on a tripod using a timer. One of us held the bike up while the other pushed the timer button and ran over to the bike to get into position. It took us probably three or four hours, but we finally got a good shot!
I saw a similar photo on the web, and loved the idea.
Hire a photographer.