We went to the Christmas market where Caga Tiós of all sizes were on sale, from massive ones the size of a small puppy to teeny tiny ones an inch or two long.
The other popular poop related tradition is the Caganer (The Shitter), a figurine in the nativity scene. Traditionally dressed as a Catalonian peasant, but can take all sorts of forms. The market stalls included pop figures, politicians, footballers, and a variety of characters from Yoda to Shakespeare.
We spent a long time looking and giggling over them. I bought myself a small traditional one, but am tempted to go back and get more.
The origins of the figure are disputed, but he seems to date back to the baroque period at least. It could just be for the humorous element or to take the piss (especially with the newer political figures), but there is quite a lot of scholarly writing around the symbolism of fertility. Ethnographer Joan Amades says:
"[Caganers were] customary figure in pessebres [nativity scenes] in the 19th century, because people believed that this deposit [symbolically] fertilized the ground of the pessebre, which became fertile and ensured the pessebre for the following year, and with it, the health of body and peace of mind required to make the pessebre, with the joy and happiness brought by Christmas near the hearth. Placing this figurine in the pessebre brought good luck and joy and not doing so brought adversity."
Even the City's official Nativity display had one. He traditionally hides round the back, so it's not as though he takes front and center, or upstages anyone, but you still know he's there.
Apparently there was a row in 2005 because the city chose not to include a Caganer in their display... reportedly due to the city's new bylaws which made public urination and defecation illegal (though the city later denied this.) The Caganer was restored the following year.
The non-poo-related highlight of the day was a visit to the Museu de la Xocolata... but even there there were white and dark chocolate Caganers to be had. There may not be a lot of public toilets, but Barcelona is otherwise a city after my own heart!