Armband for running in the rain

Hi,

I have an iPhone 3Gs and live in Seattle and I'm hoping to purchase an armband to run outside with. Naturally it'll rain sometimes. I don't need one that's completely water proof (or do I?) as I won't run outside when its pouring.

Any suggestions for an armband?

Also, is it worth it to get the Nike+ blue tooth accessory or to use some of the free apps in the app store such as trailguru.

Thanks!

be careful what armband you get. I bought one ($29.99) I hated it ,It rubbed constantly on the inside of my arm, when I ran very irritating.