There are several things, but what has been most significant is figuring out why the items in a site ended up where they were. I've excavated several Hohokam pit houses that burned accidentally and everything was left on the floor. Those scenarios are archaeologists' dream finds because it's like a time capsule. It's not the individual items that are important, but rather the context in which they are found.
Probably the funniest thing we ever found was what is called a Hohokam phallic stone. Yeah, it looks like what it sounds like. Most are about 4 to 6 inches long, but one day on the site, the backhoe operator came over with one that toppled out of some dirt he was moving. It was about 16 inches long and almost 3 inches in diameter. As he walked up to me, he said, "Don't ask where the batteries are." We did a display later for Arizona Archaeology Month and had the item on the table labeled as an "Unusual Ceremonial Object." We actually had found that label in an old book of artifacts. An older woman was intrigued by it and kept saying, "oh my, oh my" once she realized what it was.
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