Google Street View Trekker
Niall Kennedy stashed this in Google!
Google shrunk its Street View data and photo collectors into a backpack-sized package and has started mapping hiking trails! They mention starting mapping trails in the Grand Canyon (donkey mounted?).
Google also announced offline storage of maps data. You should presumably be able to combine trail maps + satellite + Street View Trekker of trails all stored on your phone.
Pretty soon it might be someone's job to go hiking with these things. Or they just loan them to rangers.
Some more info from Engadget:
Weighs 40 pounds. Uses a low-power computer with Android onboard. 15 5-megapixel cameras.
Google may rent out the backpacks after an internal trial run with Googlers.
Do you think they'll be able to get them under 5 pounds in under 5 years?