I've completed the Main Questline (with ZERO gratification for destroying the worlds greatest evil, thanks) the Civil War Questline (again, nobody knows who I am), the Thieves Guild Questline (NOW they've heard of me, but don't know it's me they're talking about), the Dark Brotherhood Questline (Nothing again) and I'm half way through the Companions. And I can't buy the add-on's for another two weeks.

I need some fun stuff to do, because frankly, I feel like I'm running out of things to do in this game. I'm close to trading it with a friend. I need a reason to keep hold of this game. :/

Any ideas?

Do you roleplay? If you don't, get into that. It adds a lot to the game, really.