I've been playing with the idea of creating a mod that would allow for making all the missing grenades in the game - Cursed Frost Grenade, Blessed Firestorm Grenade, etc. - and I've got the basic outline for how it could be done in my head (or at least how I'd expect it to be done), but before I even get started, I'd have to make sure I can actually make icons that would be appropriate and doesn't look out of place (which is frankly unlikely).

Anyone that's written a guide on how to do that yet, or care to give some pointers?