Automatically set bidi-display-reordering?

Can someone help me come up with an easy way to change my buffers to
bidi-reordered ones, either automatically (on detecting unicode
reordering commands, or consecutive Hebrew characters within certain
file types), or semi-automatically, using a per-file local variable
setup.

I tried putting this at the end of my files without success.

 /* Local Variables: */
 /* bidi-display-reordering:t */
 /* End:                     */

Additonally:
I haven't even been able to figure out how to map a key to set a variable

(global-set-key (kbd "<f2> b") '(setq 'bidi-display-reordering t))

For now, I just type a (setq ...) right into my buffer, evaluate it
and then  kill the line.

Scot