Yup. Several times.
I had this awesome backpack in highschool that was a pretty brown/rust/olive/maroon/cream paisley with fake leather trim. The fake leather went all to hell on me, so I salvaged the tapestry fabric and made an envelope bag, and made a new strap for it out of satin cords and tassels (for upholstery and draperies). I used a home-made frog arrangement for closing the flap of the purse. That was my first ever home-made bag.
More recently, I made a backpack out of an old jean skirt that always looked like crap on me and was hard to walk in because it was too straight, too long, and didn't have a vent or any kick pleats. I installed a zipper inside of the waistband, so that the top of the bag could zip shut. Then I sewed the hem of the skirt shut. Using four cheapie webbing belts, I put one around the bottom, so I could buckle the bottom of the bag around my waist to keep it from slipping when I was on my bike. I put one through the belt-loops as the skirt, just because it was cute, then I used the other two for the shoulder straps. I sewed the blunt end of the belt to the top waistband of the bag, and the end with the d-rings is loose at the bottom and threads through the bottom belt, so I can adjust it. It is hard to explain. When I get new batteries for my camera, I will have to show y'all. It is actually pretty cool.
I made a little wrist-strap evening bag to use when my husband and I got married, because I knew I needed to have a few things to hand (sunscreen, lip balm, ink pen). We had an outdoor wedding and reception at the end of June, so things were pretty warm and sunny. I used two half-moon shaped pieces of white satin, with grey/peach lace overlaid on them, some 1mm pearl-bead re-embroidery, and a grey, ruched-satin ribbon for the wrist strap. My wedding dress was cream and peach, and it looked pretty nice together. The bag had a drawstring top.
I've got a bag my mom started to make for me, and I am going to finish it. She crocheted it out of brown, orange, and tan yarn (it is concentric rings/stripes of the colors) and is an envelope-style bag, with a long double-strap that ends in a tassel on either side, comprised of 4" pieces of the yarn and some wood and brass beads. The flap of the purse is held shut by a yarn loop and a large wooden button. I'm going to line it in brown satin with a built-in change purse and a zip across the top. I may also make a separate little pochette for makeup and small items that would match the lining.
I have some cool old 1970s patterns for bags and some more contemporary ones that I might have a go at. I have a big piece of black vinyl that is begging to be put to some good use, so we shall see.