Best way to compare folder contents?

[AngelicKnight]

I'm about to do some googling on this, but wanted to ask here first. It's a little question, usually something I don't give much thought too.

Consider the situation: You have a 10GB folder you need to copy from an external drive to an internal drive over USB. After an hour of xxcopying it over, the results read that of the 1,000+ files successfully copied, 38 failed, and you have no logs available to show you what failed.

So, instead of wasting an hour trying to recopy, is there a way you can compare the folders against each other to identify which files they don't have in common?

As in does anyone know an app that accomplishes such a task?

/edit -- Ok, answered my own question:

http://www.scootersoftware.com/moreinfo.php?c=features

I found that to be a good solution, gave me all the info I needed.

Still open to better suggestions though...