Anya Marina sounds somewhere between Sia and Lykke Li; it is pretty awesome.
Apparently her songs have been featured on a few shows already, though I just heard of her now.

edit: There actually is a video out for this but I had no idea how to embed it

Anya <3

"Miss Halfway" was featured on Grey's Anatomy. Her new album is really spectacular. I'm completely in love with "Not A Through Street".

Anya, Sia, Lykke Li..... Woah! Slow down Keke. ATRL isn't ready for all these good artists all at once.