I have always found Ooparts interesting; mostly because they challenge Evolutionism. Most in the scientific community will not entertain them because to do so would be career suicide. And no one wants to undertake the task of trying to reconfigure history to accomodate them.
If you are not familiar with Ooparts, they are defined as:
an object of historical, archaeological, or paleontological interest found in a very unusual or seemingly impossible context that could challenge conventional historical chronology by being "too advanced" for the level of civilization that existed at the time, or showing "human presence" well before humans were supposed to exist.
1820 From The American Journal of Science and Arts, 1820 comes the account of an ancient tool discovery. At a quarry near Aixen-Provence, France, in 1788, 40 or 50 feet below ground in a layer of limestone were found coins, petrified wooden handles of hammers, pieces of other petrified wooden tools, and a quarrymen's board. The limestone was 300 million years old.
Here's a list of recorded discoveries: http://s8int.com/page12.html This is just one of many sites out there, but I thought it was a pretty comprehensive list.
What they suggest is that we are clueless as to the evolution of man, and that man has indeed evolved not just once, but over and over again. It raises many questions; if they are authentic and indeed represent many advanced civilizations past; then what happened to those civilizations, and how did man re-emerge and re-establish themselves after their demises?
Definitely a lot of fun to ponder the possibilities.