This is really more of a Stargate: Atlantis thing, but it definitely goes with the other one, and it was in SG-1 that the Asgard all died.

My dear little Novak,
(I will call you little, though you're huge)
I've been weary unto death

I can't say I'll miss you.
That would imply an afterlife.
And I've been lingering after life

Oh, my people have given up on living like this.
We're the last of a long long line, and we won't be missed.
We are all going to die,
And it's easy to see why.
We are simply no longer alive.

I know it's been tiresome.
A Tau'ri can hardly follow on.
But your understanding blossoms like
Spring flowers.

And you have tried hard, child.
Your work has been satisfactory.
I know I've never told you, but
I am proud.

Oh, there's no use crying over every mistake.
You just keep on trying 'til you run out of cake.
Trust Colonel Caldwell for the plan
And do the very best you can
And make sure that you are still alive.

While I've been dying, you've been still alive.
When I am dead, you will be still alive.
And I am happy that you're still alive.

Still alive! Still alive.

(On the theory that the airmen aboard the Daedalus play Portal in their off hours, and that ear worms affect Asgard the same way they do humans. "Still Alive", the maddeningly persistent theme song to Valve Corporation's computer game Portal, was written by Jonathan Coulton and sung by Ellen McLain. This is just a parody, or an homage, or something. And while I'm issuing disclaimers, I don't own the rights to any of the characters, or to the Stargate universe as a whole, either.)