DEWENWILS USB Rechargeable Book Light for Reading in Bed, LED Book Reading Lights with Clip, Perfect for Bookworms, Kids, Warm White, Brightness Adjustable (Blue)

It looks interesting, but it uses three button cell batteries. I think that means you're going to go through a lot of batteries. I would love something this small with a rechargeable battery, but I don't think such a small device would fit a battery with a decent run time. This one isn't quite as small, but it does have a rechargeable battery (and it's a bargain): https://www.amazon.com/dp/B07N2W2FRZ