I have, while speaking to some of you on the phone, mentioned the yellowish haze often hovering over Denver. The photo below is an attempt to capture what I am talking about and was taken on December 10, 2008, which was a worse-than-average day in terms of appearance. It was not, however, the only time I have seen it so bad.
Downtown is to the left of the scene captured (the buildings at the left edge of the photo obstruct the view of downtown).
Enjoy that fresh mountain air!