I bought waterproof-breathable vinyl-coated nylon fabric in Vancouver at a shop specializing in fabric etc for outdoor gear, Outdoor Innovations. Finally, many years later, I’ve sewn in into an extremely lightweight poncho (See & Sew B4266 with a longer back). Sewing with this fabric was both wonderful and awful: wonderful for keeping a fold briefly pressed just with my fingers but awful for being so thin that I had to hold it until tension to help the sewing machine feed properly. Worth it and I’ll definitely look for more projects with it (tarp tent maybe?).
For waterproofness, I tested the fabric against my North Face Hyvent fabric jacket (unfairly really — hyvent is roughly three or more times heavier than my poncho fabric) by sitting a cup of water in a synched pocket of fabric. After half an hour, the lightweight fabric let through a small puddle of water while the hyvent was just starting to think about sweating (not damp feeling quite). Still, after seam sealing, I figure since the poncho can sit above the backpack straps — the pressure of the straps makes water leak through my hyvent jacket — it may still keep me dryer in a long hike in the rain. Reports to come after some in the field testing!
…and other projects including a stretchy jean jacket (so comfy! but I’m not sewing with thick and stretchy fabric until I forget how annoying it was to work with — worse than silk), my first ever shorts (so cute! again stretchy fabric is more comfy) and a somewhat more formal dress in stretchy gray that let me skip the zipper (not sure when I’ll get to wear it though!).