So, just read in a post below about a cool shortcut:
CTRL+play(spacebar didnt do the trick BTW)
to "force play" effects without rendering, at half frame rate
Very nice, really helpfull when (rough) compositing at offline stages

got any more cool shortcuts we should be aware of ?

Thanks
Lior

Premiere doesn't really let us add our own short-cuts, so you aren't missing many.

The Scroll Lock key toggle the type of playback from accelerated to force play all. With Scroll Lock active, it is the same as Ctrl+Spacebar.