Travis - that's a really good tip on the Platypus water filtration unit. I am going to be replacing my "hand pump" Katadyn unit with one of those for my next trip. I've had no problems at all with the Katadyn unit, but I like the concept of "keep it simple stupid" and since gravity will always work, I'm going that route.
I still personally have not gotten a SPOT yet - mainly because I have read so many terrible reviews on them over the years. I'm sure there are plenty of people who have had good experiences, but when it comes to an emergency situation, I want something that will work as close to 100% of the time as possible and the number of complaints for the SPOT are just too high for me. Other personal locator devices seem to be quite a bit more $, but there are some really reliable ones out there - I just have to decide on the right one.