We just launched a new public web site and spent almost an entire week FTP'ing over the content. So how to check that it all arrived intact? - let Zoom Search spider it whilst set to only show Warning and Errors in its status log.
The speed at which it was able to identify the few links to missing files in a collection of over 10,000 pages was phenomenal - worth the money in its own right. A fantastic multi-purpose tool.