[Pewpewarrows]

MetroTwit is the only other app with a great new Metro UI that I've found.

[fmystic]

Don't forget Zune, the OG metro app. Or alternately, the hipster of metro ('was into it before it was cool')

[erode]

There are several, they just don't get much attention these days.

[revolutions]

Do you have a list or such? I'd love to use these. I've only seen MetroTwit, Zune, and this.

[byproxy]

http://code52.org/DownmarkerWPF/

That's one I stumbled upon a while back.