Un’altro programma interessante è dupseek.
Interessante perchè offre diverse opzioni di intervento ed facilmente ” scriptabile”.

Usage: dupseek [-OPTIONS [-MORE_OPTIONS]] [-] [PROGRAM_ARG1 …]

The following single-character options are accepted:
With arguments: -b -f -m -M
Boolean (without arguments): -h

Options may be merged together. — stops processing of options.
Space is not required between options and their arguments.
[Now continuing due to backward compatibility and excessive paranoia.
See “perldoc Getopt::Std” about $Getopt::Std::STANDARD_HELP_VERSION.]
Dupseek ver. 1.3
Recursively scan one or more directories for duplicate files.

Usage /usr/bin/dupseek [-h] [ -m ] [ -M ] [-b ] [-f ] …
-h Print this help message
-m Ignore files smaller than min_size
-M Ignore files larger than max_size
min_size and max_size accept k, m and g modifiers
for kilo, mega, and gigabytes. Default is bytes

-b Automatically perform actions, without
prompting the user interactively.
batch_mode can be one of
report: Print a report on the duplicates found.
The format defaults to ‘full’ but can be
specified by -f format
delete: Keep the first file of every group of
duplicates and delete the rest
kill: Equivalent to ‘delete’
link: Like delete, but substitute duplicates
with symbolic links to the first file
-f Output format for report batch mode.
format can be expressed in mnemonic form or by
a sequence of flag characters.

Flags are
d (duplicates): Skip the first file in any group
h (header): Print some information on each group
n (newline): Separate groups with a newline
s (simple): Print filenames
e (escape): Escape special characters in file names

A mnemonic form can be one of
full = hn For humans to read
simple = n For automatic parsing
xargs = dne The output can be piped through xargs for
advanced removal or other processing

SAMPLE USAGE:
- Interactive search:
/usr/bin/dupseek dir1 dir2
- Same as above for files of size at least 1 kilobyte:
/usr/bin/dupseek -m 1k dir1 dir2
- Same as above for files of size at most half a gigabyte:
/usr/bin/dupseek -M .5g dir1 dir2
- Keep only one copy of duplicate files:
/usr/bin/dupseek -b kill dir1 dir2
- Substitute duplicates with symbolic links:
/usr/bin/dupseek -b link dir1 dir2
- Use backtick expansion to move duplicates to /trash:
mv `/usr/bin/dupseek -b report -f de dir1 dir2` /trash
- As above, but with xargs:
/usr/bin/dupseek -b report -f xargs dir1 dir2 | xargs -i mv {} /trash

Pressing Ctrl-C during interactive processing, you will be presented
with partial results.