What do you do with DNA from dead animals? (Other than eat it, of course, along with all the other components of meat). You track it or reproduce it.
The tracking is being done by a pair of brothers, one an English professor and the other a biologist, to try to date medieval manuscripts. The idea is that you extract cellular DNA from deep inside parchment pages of very old books. Before paper was common, European books were written on parchment made from the skins of calves, lamb, and young goats. You have to go "deep" because any DNA found on the surface tends to belong to mice, insects, or human hands that have wandered across the pages.
Once the DNA is extracted, you can identify the animal it came from. This can then be compared with a databank of known parchment-producing animals used in other books. Some of those books have known publication dates, so if you can find a match, you have a pub date. Or at least a date for when that particular page of parchment was produced.
The other current DNA story is both more contemporary and more commercial. A couple has had their dead dog reproduced by cloning -- the first instance in the U.S. of a commercially cloned pet dog (cats have been done before). It cost $150,000 to clone the Labrador.
I would not have my toy poodle Cosette cloned -- and not only because I don't have a spare $150,000 sitting around. Don't these people realize that identical DNA does not mean an identical pet? Now, if I could genetically alter a new Cosette to not hog the entire bed at night....
No. Not even then.