So, I've been dreaming of making a new duvet cover with some thrifted sheets ever since I saw Amanda's version.
I have yet to find the perfect vintage cotton sheet or fabric and I've been looking for at least two years. I have found some awesome vintage cotton pillow cases however and now I'm trying to think about a design that I can make that will be a little bit quilt like, not be too much work and be sturdy enough to last another nearly 15 years. It looks like French seams will be the way to go for some piecing to ensure sturdiness.
Here are some inspiration photos:

sweet strip quilt by skilly laminx

Patchwork Duvet Cover by rose hip

gagavida's fuzzy patchwork

mostly I love Spool of Thread's ruler wall

shim & sons' clean pattern on white inspiration is indeed inspiring

wide strips seem like an efficient way to get a quilted look

some other inspiration from Flickr
the start of habit of art's strip quilt is also very cute