Like EdT, I've carried two SLR Bodies, lenses and tripod into the backcountry. I just sold my DSLR and equipment and bought a Canon SX50 Superzoom. 24-1200 50x zoom. Just dropped to $169 on the Canon refurb site. Yes, you lose the awesome dynamic range of the large sensors, but the ability to actually use the magnification is incredible. Anxious to try it in the field. In many instances it will be better than a spotting scope. Plus, I think it could be fun at the range, too.
It won't slip in a pocket, but everything you need is in one small package. (Nikon just released one that goes to 93x optically.)
Check out the reviews at dpreview and cameralabs.
