Yesterday's weather was absolutely gorgeous so a group of us decided to spend the afternoon out at the Reservoir. We came armed with quilts, a Frisbee, books and even a bottle of wine (which we forgot to drink). Anticipating a warm day in the sun I brought my favorite
Nalgene Bottle filled with filtered water (it's not a good idea to drink the water here) and placed it in my bag along with the usual camera, ipod, day-planner, phone, book, etc... you get the point. Up until yesterday I believed all Nalgene products to be 100% leakproof...that is not true. After about an hour of springtime bliss I reached into my bag to retrieve my book and found it floating. Thanks to quick-thinking and helpful friends nothing was permanently damaged, although my day-planner is now wrinkled from April to June. This morning I looked up my favorite bottle and found that because of it's great design "this easy, one-handed access means the OTG can't be 100% leakproof ".

So while I agree that this is a great buy, you should follow the advice of the folks from Nalgene and "don't put it upside down in your backpack".