Adafruit Flex Perma-Proto - Half-sized Breadboard Flex-PCB is a classic perma proto design from Adafruit which is made from thin polyamide film. It's extremely bendable, and you can cut it easily with scissors. It has a bend radius of 1cm or better and you can solder any components to the pads.
Adafruit Flex Perma-Proto is really floppy, so you may need to support it if you solder electronic components on, it won't stay 'straight' on its own unless given some sort of physical support.
Adafruit Product Page: https://www.adafruit.com/products/1518