I recently participated in a Bridal Brunch and the Yotel in New York and one of the sponsors was Party Flops (just a note there will be a computer generated girl that pops up but she goes away). What a great idea for those beach weddings/destination weddings.
Party Flops will customize your flip flops and the styles are endless. Designing the flip flops is in 5 steps, or you can use your own design, it's easy.
This is one of the best favors that your guests will use.