Something I found out about Psychotroke Grenades yesterday in a game is that they work on vehicles. Because the wording for Psychotroke Grenades says if you are assaults or is assaulted roll a D6 for each enemy unit being assaulted or assaulting.
He charged into my Sisters of battle Immolator and the side filled with gas that made them turn off the engine in the middle of a ton of stormtroopers. Thank god for that 6+ invuln or I would have lost the tank, it was just barely able to drive away before a melta-gun came for it.
It doesn't say just infantry or excludes vehicles/monterous creatures, so they can also work on knights. Some effects are better than others like making a unit fight at I1 or only have a max of 1 attack and you auto hit them. But it is fun to see what happens and could be useful to know if you want to try and slow a knight down a bit or charge into a rhino.