As a side project, I have been filing away images to make a satellite version of the ABCs. I have most letters now, but I could still use help tracking down good examples of B, G, F, K, and Z. Since I first posted about the search, there is a new browsing tool available — called Worldview — that I highly recommend. Once you navigate to the site, just make sure you have a MODIS true color layer (either Aqua or Terra) turned on, and you can quickly start browsing for cloud formations, dust storms, smoke plumes, and much more.
When you find a letter, click the permalink button on the upper right (it looks like two links of a chain), and then post the url in the comments section below. Another great place to look is the astronaut Earth from Space gallery curated by the Johnson Space Center. The “Earth-Human Interactions” section might be especially useful for finding the straight lines needed for an upper case F, K, or Z. Though I am still missing those five letters, feel free to send any you find. Perhaps you’ll find a better example than what I already have. Good luck and happy hunting!