Andrew M.wrote a review of Nikwax Tent and Gear Proof on February 23, 2009
used it on my 10 year old timbuk2 bag (i had some of my stuff soaked in the last rainstorm), and so far so good. water beads up and slides off mostly. the underside doesn't do so hot as far as the beading up, probably because it's gotten dirty from setting it down. but i haven't had any water leak through yet.