I'm not doing anything new this year, but as Grab says you play them so rarely you never really learn them, so I am trying to re-learn a bunch to do at a Christmas concert:
Come, Mad Boys
Personent Hodie
Star of the East
The Salutation of the Angel
Babe of Bethlehem
Blessed Be That Maid Marie
There Was a Pig Went Out to Dig
Masters in This Hall
Gloria Ad Modem Tubae

JP