CMC's "Cloudscape" is a favorite challenge. I go back through it occasionally. Those stunning captures lift me out of this room to places in Chicagoland I've never been -- to colorful, wonderful cloud scenes in -- as the song says -- morningtime & eveningtime & summertime & wintertime." There's a website called "Cloud Appreciation Society" with cloudscapes from around the globe. I like these parts of their motto about clouds. "We think they are nature's poetry and the most egalitarian of her displays, since everyone can have a fantastic view of them. --- We pledge to fight "Blue Sky Thinking" wherever we find it. Life would be dull if we had to look up at cloudless monotony day after day."