I've resorted to carrying a small 3 1/2 inch x 5 inch sketch pad for my duct tape bag obsession. At the suggestion of my friend Claire of claireabellemakes.com I started to make the bag with a green duct tape. While I couldn't find a nice lime green, I did find a sour apple one.
It still needs a strap and closure (and maybe a pocket) but I think it's looking okay.