In its few years of existence, the virtual globe program Google Earth — which allows anyone with Internet access and a personal computer to zoom in on recent satellite images of almost any point on the earth's surface — has attracted millions of enthusiastic users. Among them, according to a recent Wall Street Journal article, are commercial roofers, real estate agents, landscapers, and insurance companies, who use the program to make rough estimates and scout for new business.

Was the architect also a quilter? Or did the owner of this French commercial building award the reroofing contract to a low bidder with a warehouse full of leftovers from previous jobs?

But Google Earth is also just plain fun to explore, as evidenced by the number of related Web sites where enthusiasts post the coordinates of favorite discoveries. Some devotees spend hours each day searching satellite images for airplanes captured in midflight. Others are captivated by crop circles or overhead views of celebrity homes. There's even a community of determined users who scan the world's nude beaches for tiny but recognizable human figures — quite possibly the hardest way to find naked people in all of cyberspace.

Soon after construction began on this cluster of four L-shaped buildings at San Diego's Coronado Naval Base in 1967, the Navy realized its swastika-like shape could present problems when viewed from above. However, it wasn't until last fall that officials announced a $600,000 renovation to disguise the complex with landscaping, walkways, and solar panels.

No doubt a few phone calls to Christchurch, New Zealand, could prove or disprove the obvious hypothesis that this distinctive structure is home to the southern hemisphere's largest manufacturer of circular-saw blades. But it's more fun not to know.

And then there are building-related images like the ones shown here, which don't necessarily fit neatly into any particular category but are worth looking at because they make us smile, raise unanswered questions, or call forth the sense of relief we all feel, on gazing at someone else's gigantic mistake, that it wasn't ours. — Jon Vara

A warehouse-like structure near Nairobi, Kenya, seems to extend a cheerful greeting to all who pass over.