Tech Support Pits:

From Claudia===
Dear Webby
I need a quick and simple way to de-duplicate thousands of
midi files that my mother accumulated in hundreds of 
directories. Her machine is literally full and none of the
storebought de-duplicators work without ample room.

I can connect my laptop to her machine with a cross-over 
cable like you suggested a few years ago, but those 
programs don't work across multiple machines. 
HELP!
Claudia

Dear Claudia
Make a folder on your machine and call it Moms-Midis.
Then go onto her machine and do a search for 
*.mid
Open a file explorer window showing your machine and the
Moms-Midis folder.
Click in the search window and hit CTRL A to select ALL.
Let go the CTRL, hold down the SHIFT and drag ll the midis
over to your machine and into the Moms-Midis folder.

At the first duplicate it will ask you if you want to overwrite.
Click on "Yes to ALL"

After that has completed, sort the midis in the Moms-Midis
folder by SIZE. Whenever you see a bunch with exactly the 
same size, check the file names. You will probably find 
quite a few that have the same size but slightly different
spelling. If "DustyRose.mid" and "Dusty-Rose.mid" have the
same size, it's safe to assume that they are the same piece
of music.

There is no point sorting by name. If the file size is 
different, then they are not duplicates.

After you have deduplicated them, then you can drag the
entire Moms-Midis foler over to her machine. It will have
plenty of space for it, since you had moved all midis off
it earlier on. 

Have FUN!
Dear Webby