We never had one of our own, but many of our friends owned doctor's kits. All of us fought over the stethoscope and the syringe! Not only is it fun, a set of pretend medical accoutrement can help prepare your child for his next doctor's visit.
We've shopped around and really like this doctor's suitcase by Erzi. The kit is made of wood and includes a realistic stethoscope, a syringe, wooden scissors, wooden spoon, test tubes and a thermometer. The only downside is the price - $115. Otherwise we're hoping to score a vintage Fisher Price doctor's kit on eBay.