Well, it all depends on the relationship you have with your boyfriend's parents. If you're close to them, then you might want to consider getting them a thoughtful gift that shows your appreciation for their support and encouragement. Maybe something like a nice bottle of wine, or tickets to a show or concert they would enjoy. If you're not as close, then it might be a good idea to get something more general, like a gift card to a popular store or a basket of treats. Just remember that it's the thought that counts!