Scanning for Duplicate FIles

Can Anon recommend what programs are BEST for finding duplicate files?  I have quite a few and it would take AGES to actually sort through them all manually.  I want a program that can do it effectively but not delete any that are close but not exact matches.

So what does Anon recommend?  Links for extra points.

www.opera.com

If that doesnt help, try   www.file.sorter.on.nimp.org

>>2
Irrelevant links don't count for extra points....

>>4
Lurk moar.

>>1
One-liner in bash.

Surely someone has some real suggestions.

>>7
Yes, you must have somehow missed >>2, >>3 and >>6.

>>6
Say what?

Ah, winfags.