I threw a quick one together for last month's campout for testing with a simple netless gathered end hammock. Similar to one of my earlier bug net designs.
3yds - 1.0oz ripstop nylon, 68" wide
6yds - 3/32 shock cord
2 - Micro 2 hole cord locks
1. Stitch a 3/4" channel along both sides of fabric.
2. Fold fabric in half to approx 104" x 32"
3. With cover inside out, Stitch ends leaving approx an inch open at the top corners.
4. Turn right side out and put a second row of stitching on ends.
5. Thread shock cord through bottom channel and attatch cord lock on both ends.
Final weight was right around 5.5oz.
This made a quick and simple cover that cinched up against my UQ. Using the breathable ripstop blocked the wind well and provided a nice temperature boost inside the hammock for the 25 degree overnight lows.