So, we have the Drow of Eberron. Many of them throw their alliances here and there. Most of them align around Vulkoor, the scorpion god.
And then Lolth the spider-goddess shows up, literally rips a new one between the space-time fabric of Eberron and the Forgotten Realms, and then declares war on a village, using her legions of the Underdark--who seem to make the Drow of Eberron seem like a bunch of farm kids from Korthos wielding masterwork weapons and Clubs of the Holy Flame.
I don't know if Vulkoor is up to planet-killing savvy as Lolth is, but wouldn't it be great to have a quest series and raid that pits the Drow of the Underdark against the Drow of Eberron? Imagine an imminent invasion by Faerun Drow into Stormreach. One NPC Drow (Drizzt Do'Urden? ) is not pleased by the idea and works with adventures from Xen'drik to find out more and stop the Drow incursion.
"Our" Vulkoor Drow wouldn't fight for Eberron as much as to save face to show that they are Drow, too. Drider versus Scarrow fights would be naturally awesome.
The idea's based on too many "Star Trek" episodes with Klingons and the resulting post in my DDO blog.