A single cultural dance of five to seven minutes is what most newlyweds settle on. It usually comes right after the initial set of dances -- the first dance, the father-daughter and mother-son dances, and a dance for the members of the bridal party. Most bands are familiar with the music that accompanies the more popular ethnic dances; just be sure to tell your bandleader in advance what kind of music you want and when it should be played. If you expect to devote a significant portion of your reception to ethnic dancing, or if the music you desire is somewhat obscure, consider hiring a band that specializes in that genre.
Many of the cultural dances we associate with weddings today -- the polka, the hora, the tarantella, and the Greek kalamatiano -- are essentially all-purpose festive dances. Others, by contrast, are wedding-specific and tend to incorporate a lighthearted ritual; in Finland's weaning waltz, for example, the bride and groom dance with guests at the wedding in order to test their loyalty to each other.