I fully admit that when forced to make cuts to our Christmas Day service, I yanked the Wise Men, saying, "They didn't really show up until Epiphany anyway." Well, today is Epiphany, and I want to give them their due.
Every year on January 6th, following the twelve days of Christmas, the Church celebrates Epiphany. If you know it as Old Christmas, it's the same thing: not the day of Jesus' birth, but the day he was given gifts. Matthew 2 is our only record of the visit of the Magi, and the details are pretty slim. The Bible never calls them kings, actually; that seems to have gotten tacked on later by tradition. They were magi, wise men, learned astronomers and astrologers (most likely). We don't know where they came from, but our best guess is around Persia (modern day Iran). We don't even know for sure how many of them there were. The Bible doesn't say that, either, but since they presented three gifts, tradition declares there were three (one per gift) and supplied three names to go with them: Gaspar (or Caspar), Balthazar, and Melchior.
But look at the gifts. Gold, the treasure of a king. Frankincense, the offering of a priest. And myrrh, the anointing of the dead. I'd wager the wise men didn't know it -- these were just expensive Eastern gifts in general -- but their tokens point to the child as king, as mediator, and as a suffering Savior. The Holy Family may or may not have sold them to finance their flight to Egypt (it's mere speculation), but the gifts from those who followed a star teach us to give our own gift to the Christ: the gift of ourselves, living sacrifices to a risen Lord.