I've been looking for something to provide some shade on the driver's side on those hot days where you get several hours of direct sun while driving. The pull down screen provides very little protection. Often I have to pull the curtain partially closed to keep from getting baked. The down side is....the curtain will often slide forward when you slow down or hit the brakes....not good.
I've been looking for a product and found this
Retractable Sun Shade . It's made to open horizontally across a windshield. I mounted it vertically using the two adhesive tabs provided. It matches the black window frame.
There is a slotted tab provided by the sun shade company to hold it in place when it's extended because it retracts automatically. Instead of using the slotted tab, I used two tabs of velcro so that it could be quickly released/rolled up if necessary. (The velcro is on the window sill in this lower photo).
Note: This works well if you have the mirrors you view through the windshield....obviously it would be dangerous if you had side mounted mirrors.