I also got the chance to do my first bungee jump. It was fairly sketchy - they only had velcro bands around the ankles with no other security - but the fact that it was only about 50 feet or so over a river meant that I most probably would have been perfectly fine if the velcro around my ankles gave way. It was pretty fun - you got dunked into the river at the bottom, then bounced right back out. They also had a great zip line over the river.
After that it was time to head over to Bolivia. A short bus ride, and I encountered the most relaxed border crossing I've ever been to. I was the only gringo. There was a small bridge over a dry creek, with a passport office on the side. Despite it saying "Passport Office" in 6 languages (including Hebrew), I was the only person who actually used the passport office - everyone else just passed back and forth over the bridge, often pushing wagons covered in blankets, completely ignoring the armed border guards.
Once in the passport office a disinterested Bolivian civil servant manning a dusty typewriter stamped my passport with a 30 day visa without even looking at me. I'm not saying this from experience, but if you ever find yourself on the run from the law in Argentina, definitely consider the La Quiaca/Villazon border crossing for making your escape.