I will put a small RGB LED strip with 8 RGB LED's on 10 cm in my webshop soon. The PCB's are manufactured today.
It has 8 LED's on the front, and 3 TLC5916's on the back, so it is compatible with ShiftPWM.
With the LED's on the front and the drivers on the back, the LED's can be placed very close together (1 every cm). The LED side is also completely flat, apart from the LED's. So you can stick the LED's through a (laser cut) panel.