The Hunting of the Wren, was an old ritual once performed on St. Stephen's Day by the children of the village who would go out and find a wren out in the woods, kill it, and then put it in a box. They would then drape the wren in purple cloth and decorate the box with cloth and flowers and carry it from door to door, often singing a song like this one:
By your leave we will sing concerning our King.
Our king is well dressed in silks of the best... etc, etc...
There is some speculation as to where the tradition comes from but it may well date back to the Celts and the druidic practice of using wrens to divine the future.
Anyway, whatever you're doing today - whether it's hunting wrens, or otherwise - have a good one!