Plus if you are using fine metalic powder it has the added bonus of making people it hits..... all sparkly and glittery.
Right before it lights them ablaze...
Oh, wait, I'm thinking of magnesium shavings.
Would there be a problem with comibining the two?
seriously though, in the interests of completeness the other possibility I can think of which hasn't come up so far would be LIPC tech where a laser is used to create an ionized channel for the electrical charge to jump across (it's been floating around for a while as an Idea for "wireless" Tasers though to my knowledge none of them have got beyond the prototype stage (although
this could make a fun door for the Shadowrunners to get past. ) shrinking it down to grenade size would be a trick since it's effectively a two stage system: the laser and the electrical discharge, so it would probably be bulky and energy hungry but I can't think of any particular reason why you *couldn't* do it that way but barring some advancements in energy storage I can't imagine you'd be able to get it to run very long so it's probably something more suited to one of those roller drones from the espionage section rather than a proper grenade.