[The] new law says is illegal to skate, do graffiti, posters, stickers, give flyers, eat or drink on the streets, put your wet clothes on your window (to get dry), prostitution, throw up on the streets, street sellers (like cd’s, dvd, artesany, food,,,,), musicians (without permission), malabars, acrobacies, jump,,,,etc…
is fuckin’ crazy our city now is grey!!

A wide coalition protested the new laws in December. Orianomada writes on flickr:

ManiFESTAacción contra la ordenanza cívica (algo así como el TOLERANCIA CERO de New York) que quiere aprobar el ayuntamiento de Barcelona, el 23 de Diciembre de 2005, promueve limitar y reprimir el uso del espacio público. En esta manifestación estuvimos, prostitutas, skaters, grafiteros, movimientos sociales y vecinales, artistas callejeros, etc.
Rough translation: Protest/party/action against the civic ordinance (something like New York’s ZERO TOLERANCE) that the Barcelona City Council wants to approve on December 23, 2005, aims to limit and to repress the use of the public space. In this manifestation we were prositutes, skaters, graffiti writers, local and social movements, street artists, etc.

You can check out photos of the protest on flickr, and a short video on YouTube.
For all you Spanish and Catalan readers out there, here are some links to more info on the new ordinance and acts of resistance them: El carrer és de tothom (a bilingual blog in Catalan and Spanish), Cinismo, and Barcelona Indymedia.
All you English-only readers better enroll in some Spanish classes quick, because all I could find was this one English blog that covered the issue: Mudd up!