I have, from time to time, experienced opposition to my recording at a certain location. Anyone who has done any significant amount of sound recording probably has. The only way to get around this sometimes is to go through the right channels - getting permission, permits, etc... and sometimes that costs money and it always costs time. Sometimes I don't want to spend either of those, so I often find myself sneaking around with my recorder, hiding my mic to try to get certain sounds. This happens most often while trying to get certain ambiences, but sometimes while trying to get other things too. It has often led to some cool stories involving getting chased out of somewhere, getting dirty looks, accidentally ending up somewhere I wasn't supposed to be, etc...
I remember one time early in my career I was traipsing around Central Park in NYC with my recorder, mic, headphones and portabrace bag grabbing some ambiences for a short I was working on. I stumbled upon a row of 3 massive Paramount Pictures big rigs and some random crew. Curious, I followed a few of the crew members back to the set. There were PA's all around turning curious onlookers away and keeping the perimeter "safe". I had my headphones around my neck and my bag over my shoulder. I made sure my mic was visible, and walked over as if I belonged there. I nodded to the PA as I walked past her. She nodded back and I was on the set. I thought this was amazing, since I was 19 and had never been on a film set before. I spent the day there, and ended up talking to the audio guy (all Run and Gun that day), a few other crew members, and a bunch of the cast, and I snagged some crafty too! All in all, I learned a lot that day.
Anyone else out there have any cool stories about stumbling across something or a "gorilla" recording session?