Try sending them a baby balloon from the florist. Or you could get a tape of the heartbeat and play it for them. Or maybe, wear one of those shirts that says "I'm baking" or "bun in the oven" or something like that. Or send an ultrasound piccie to them. I took a photo of my postive test and was going to stick it to my mums door to see when she came home. She beat me back to her place so instead I casually left it hanging out of my bag and she grabbed it and screamed.

Bridee - I love the idea of a photo frame with the card inside saying reserved.

On the day we got our BFP (sat) we were going car shopping anyway and ended up buying one. We picked the car up on the following Monday and drove it around to the familys houses. Pulled up in their driveway and rang them from the mobile. When they answered I said 'Whos awesome car is that in the driveway? Looks great' When they looked out front to see who it was then we waved at them from the car. After they got over that, we told them the reason we got a new (better and safer) car was because we wanted our baby to be protected. It took them a few seconds to sink in but they got it in the end.