Google advanced image search
has an option to search just for faces. This means they have a program to inspect an image file and guess if it contains a face. This is something that humans are really
good at, but computers take a lot of teaching to get right and Google seems to do a pretty good job.
Straightforward uses of this include searching for a country name to see natives and visitors, checking out the hair styles of "software engineers," searching for "bush" and seeing what portion are satirical versus serious, and turning "safe search" off and finding people sucking on your search terms (like "big"). But amusement can also be found by searching for terms which (without the "faces" option) are less likely to contain faces. Sometimes the results include nonhuman images which nevertheless have a similar structure to a face. Sometimes they include a statue or drawing. And sometimes the results have really awesome human faces. Try it yourself!
Edit: A search for "geek" brings up several copies of this one: