The WikiReader does have a Forth interpreter embedded in its firmware, but doesn't run it by default. It is activated when pressing the right buttons at boot a

The WikiReader does have a Forth interpreter embedded in its firmware, but doesn't run it by default. It is activated when pressing the right buttons at boot and allows developers to access a Forth console via serial debug-cable and/or compile Forth programs from Forth sources contained in the built-in micro-SD card. As Forth is very low-level and allows direct access to memory (and thus memory-mapped registers), it makes testing hardware quite efficient (and fun). What makes you believe the WikiReader didn't sell well? AFAIR quite the opposite.