It seems to me that bamboo curtains strike a good balance with privacy and shade. They're good-looking, too (especially appealing to organic modern types). And really versatile. There's a lot you can do with a simple Roman or roll-up bamboo shade, as these photos all prove.
Mount them in front of the window
Mount them inside the window
If you want to preserve the look of your molding and the structure of your windows, this is the way to go. Just check out Simran's Uniquely Beautiful Apartment.
Layer them with curtains
Double the fun, and double the shade or privacy, like in Matt & Mel's Animated Abode.
Hang them behind the bed
With or without a window. (It could even replace a headboard.) This feminine bedroom is in Philadelphia, and was designed by Design Manifest.
Use them outdoors
Bamboo curtains on a deck or patio will define your outdoor rooms and offer shade, privacy and a way to cut the breeze, as in this outdoor dining room from DeBilt Homes.
...as a roof, even.
Drape a bamboo curtain over an existing structure, or build one to suit your needs. This is a bamboo-topped deck in Sydney from Sam Crawford Architects.
For indoors use, or outside. Bamboo curtains don't have to look so "natural" if that's not your thing. Just check out the black bamboo curtains in this glam German living room, from Piazza Wohnkultur via Houzz.