Ok owing to my knowledge of physics, weapons and a few other fields I found it highly amusing when reading the deathwatch core book pg. 28 where a marine sergeant informs some scouts that a bolter she'll has a 'depleted deuterium' core.
Knowing what I do I would guess depleted deuterium would by either hydrogen or helium. I assumed the guy who writes the stuff just thought along the lines of depleted uranium but assumed deuterium wad more advanced.
Of course the sarge may have believed it was deleted deuterium, being told that by a tech preist or tech marine who then went to laugh his implants off. Or because keeping 'em ignorant is just imperial SOP.
so what in deathwatchn has amused you
the most?