One of the things about Lent that I think attracts people is its symbolic power. Nothing at all changes from Mardi Gras to Ash Wednesday, but the season of Lent seems to take hold of that first day and stake a claim to the next 40 days. It's the one day a year that people (at least in Chicago!) walk around confessing their faith: "Yep, I'm one of those." And I suspect that even those who barely darken a Church door most Sundays feel the tug and try to "do something for Lent." That slight dusting of ashes has an amazing power over us!
Come to think of it, this is only one example of what can only be called the "embodied spirituality" of Catholicism. Not that we're the only ones with it: the Jewish traditions are powerfully sacramental, in that "the visible reveals the invisible" sense. (In reading the novels of Chaim Potok some years back, I was really struck with how "familiar" the Hassidic mentality is to Catholicism: it's sacramental!)
The Theology of the Body is the most all-embracing (pardon the pun!) expression of the Church's sacramental world view, but that same sense of the "embodied sacred" is also why Catholics say grace before meals, wear medals and scapulars and bless themselves with holy water (or candles, on St. Blaise's feast day) and pray the Morning Offering (which offers the day's most ordinary "prayers, actions, joys and sufferings" right alongside the offering of the Eucharist).
It's not just the sacraments that are sacramental! Catholic life fully lived is fully sacramental: a visible expression and presence of the living, risen Lord Jesus, all in the "sign language" of the body.