I think the hammer and spark plugs are the funniest. The question is whether they were found in-situ? And they are not. Besides, spark plugs were not around at the time of Noah and his world wide flood. One does not even need to take a single course in geology to get an idea that something is wrong this argument. Spark plugs have been aroung for only 50 years or so :)
I could find some strata that are of pre-cambrian age, dig a hole and place a Verizon Wireless phone in there and cover it up. Then lead a geologist to the site and ask him to dig there. Wow what an amazing find!! Perhaps there were aliens around 3 billion years ago that had already invented cell phones and used them for communication?:)