Today is the last Sunday before Lent. Depending on your tradition, it may be called "Last Epiphany", "Seventh Sunday in Ordinary Time", or probably some things I've never heard. I grew up calling it "Quinquagesima", which roughly means "Sunday within 50 days of Easter." At any rate, in the more-liturgical Christian denominations this is the last Sunday until Easter on which "Alleluia" can be sung or said as part of the mass/service/liturgy. I even have heard of places where all the special music for Easter had to be fully rehearsed by today (well, OK, by Tuesday) because nobody was allowed to even practice songs containing Alleluia between Ash Wednesday and Easter.
I don't know of anybody today who is quite that stringent, but I do like the custom of saying Farewell ("Vale" in Latin) to Alleluias by tossing a good number of them into the music for Quinquagesima. My favorite case of this was a couple of years ago when we happened to hit this Sunday at Arwen's parish. Alleluias were liberally distributed through all the songs, capped by Song of Thanks, in which the chorus consists of "Alleluia" repeated sixteen times. Since it also has six verses (and they sang all of them) and starts with the chorus, that was 112 of them. Almost enough to last me till Easter!
Unfortunately, in my current parish the music director -- although a wonderful and talented person -- is a convert not raised in any church, liturgical or otherwise. The rhythms of the church year are not something that come naturally to her. So the only Alleluias the choir sang this weekend were in the Gospel Acclaimation. (It was a good long one.) So I'll sing some to myself these next two days, and then reluctantly bid farewell to Alleluia. Until Easter!