On some systems I get an error dump with comments about being unable to create enough virtual memory, but it seems to be related to very deep directories with very long directory names. I don't know enough to try to debug it.

I'm looking at [link|http://www.tucows.com/preview/373411|Duplicate File Finder 1.1.0.0] right now. It's very well done, very fast (even when calculating CRC32s), has a nice GUI, and has lots of output options. It seems nearly perfect for Win32. The price is right too - it's free.

It had no problem with my T41 laptop. I'm having it search my Opteron box now - it's got ~ 2 M files with a sizable fraction being duplicates...

Cheers,
Scott.