water

LifeStraw ($19.95 MSRP) is a water filtering straw that allows you to drink water from a questionable source while camping or adventuring.  It’s portable, and you can put it in a case (either by LifeStraw or third party) after use to keep the inside of your pack dry, and it lasts a long time (1000 gallons of water). I like this because it is compact (9 x 1.2in – 22.9 x 2.6cm, 1.6oz – 46g), it lasts almost 3 years of daily use at 1 gallon per day, and the maintenance when you get back to civilization is easy.