OK, let me state first of all that I'm not asking for code (although all donations gratefully recieved), just general advice as to how to go about a particular task.
I have in my possession 36 text files that look like this (only longer): 
-0.29
-0.39
-0.51
-0.65
-0.85
-1.07
-1.33
-1.66
-1.92
-2.11
-2.21

[download]
And I want to be able to write a perl script that will randomly select 3 of this files and print the contents of the remainder (i.e. the other 33 files) into one file like this 
-0.29    -0.2    0.62    -0.82
-0.39    -0.25    0.79    -1.05
-0.51    -0.34    0.97    -1.35
-0.65    -0.46    1.15    -1.67
-0.85    -0.64    1.34    -2.07
-1.07    -0.86    1.57    -2.55
-1.33    -1.07    1.8    -3.05
-1.66    -1.33    2.05    -3.64
-1.92    -1.57    2.21    -4.28
-2.11    -1.77    2.23    -4.91 etc ... for 33 files

[download]
I want to be able to do this a number of times until all combinations have been covered ensuring that a particular 'three file combination' is only chosen once (of course any file can, on its own, be chosen a number of times, but only once in a particular combination of two other files ... make sense?).
So far, my logic on how to proceed is as follows:
Rename the text files 1 to 36 and then chose a particular three way combo using a random number generator. A flag would then have to be created .. perhaps a variable that is unique only to that particular 3 file combo ... which is set to 1, to ensure that this combo is not picked again.
The end result file is then created from the remaining 33 files.
Logical or not? Any advice, pointers much appreciated.

In reply to randomly selecting files by Angharad

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