Most YEC arguments center on problems with millions of years, such as salt in the sea, short-period comets, spiral galaxies, etc. These are all fine and good since a young world fits within the limits these clocks put on the earth. But there are a handful that actually point at or near 6000 years. Well, we now have another one, and it is powerful. Check out this graph:
Note that each data line represents predicted levels of helium diffusion given a 6000 year old model, and a 1.5 billion year old model. The RATE group has received their data from an independent lab, and look where the data lines up! If this isn't compelling evidence for a young world, I'm not sure if anything would convince Old Earthers. This is how science should work - A prediction is made, the experiment is run, and the result is checked against the prediction.
From the article:
The experimenter, being a uniformitarian (believer in long ages) and not having read our prediction, had no idea what results we were hoping for. ... To our great delight, the data fell right on the "6,000 year" prediction! This alignment validates the young-age model even for readers who are not experts in this field, because the probability of such a lineup by accident is small. The data resoundingly reject the "1.5 billion year" model. The experimenter, whose name is in one of our articles, stands by his data, even though as a uniformitarian he does not like our interpretation of them.