I'm a bit curious when reading all the posts here and elsewhere on the web regarding overstaying a 90-day tourist visa.
People talk a lot about stamps in passports instead of computer records of entries and exits. When I left Spain I watched the immigration officer and when he typed in the person's name, a varying amount of lines came up on the screen on his computer, in green. My guess is that maybe sometimes those lines a red or something and that means trouble. They must keep computer records, it's not exactly rocket science...
Maybe they still don't care, but I wonder if things have changed much since all the recent terrorism. If anyone has recent experience, maybe the last year or so, of overstaying your tourist visa, please reply.