I have a new stock of cuben fiber stuff sack style dry bags built and ready to ship. These were built using the standard grey color cuben fiber with a piece of 2mm cord and a tiny cord lock up top. They are 100% bonded and the top can be pulled really tight but are not submersion proof dry bags. They work great for keeping the weather out of your gear and will work perfect for 95% of your outings, but I don't recommend using them boating, kayaking or river rafting.
In addition to the stuff sacks I built a tent stake sack that is 3" x 8" and weighs about 5 grams. The introductory price is $7.95 so they shouldn't last too long.
More info is on my website so check them out. If you have any questions please feel free to ask.
A grommet is used to keep things strong and clean looking
Detail of how tight you can snug the top making the bags completely rain-proof.