When wedding crashers show up on your special day, it's not always the best experience in the world. After all, they can cause quite a bit of chaos! But when those visitors turn out to be celebrities like Jon Bon Jovi or President Barack Obama, it can be the one highlight that makes your ceremony all the more memorable!
Click through the gallery to see which lucky newlyweds got to celebrate with a celebrity on their wedding day!
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The Science Guy was more than happy to join these newlyweds' photoshoot while he was out for a bike ride!