PBL Strategies

I am wondering if anyone has any experience with utilizing project-based learning in their schools.  It is a trendy buzzword these days, but I feel that many schools and teachers simply like to say they do it, while in reality it is not used very often.  Even the schools that I have observed that do PBL very well do not tend to use it that frequently.  I wonder if this is a strategy that will end up being much larger than it currently is, or whether this is something that will die out over time.  Providing students with opportunities to learn by doing seems like a great idea, but it also seems to go head to head with prepping the students for high-stakes testing.  It seems to be quite a challenge to accomplish both things, drilling the students so they are adequately prepared for tests while also providing them with hands-on activities so that they can explore the curriculum in less traditional ways.  Has anyone seen PBL done in a way where it is both frequent and meaningful?