In the "Waves of Madness" world event you can get a "Vial of abyssal water" that adds a glow effect to your weapon. Like most special items in Rift the item description is less than helpfull and they forgot to mention that it's limited to 24 hours.
Are there any way of obtaining a permanent weapon glow effect in Rift?
Update:
In later world events, at the moment "Planar Menace", it is possible to buy epic quality item Endless Overgrowth Oil that is bound to account and have infinite charges, that give a 24 hour weapon glow effect. That is 24 hours game time, so in practice it will last for several days or weeks. And when it runs out it can be renewed infinitely for all your alts on that account. That is good enough for me ^^
Best Answer
Currently there is no permanent glow effect for weapons. Preorder runes for weapons have a glow effect based on the elemental resistence the rune will give.
There are also some runes for just giving the weapon a glow effect for a limited time like the "Vial of Abyssal Water" you mentioned (the River of Soul world event had a similar rune).
Afaik there are no crafted runes that will give a glow effect at all. I have a maxed runecrafter and quite some epic and rare recipes but not every recipe out there so i can't be sure.