First, can you guess what the following code does before running it? ... 
    1x~@;

[download]

This node by shmem gave me the idea, and may give you a hint as well.

Now for the challenge ... what's the shortest program which does the same thing?  My guess is the obvious:

<Reveal this spoiler or all spoilers in this node or all in this thread>

How about the smallest program that does the same thing slowly?  The following takes about 11 seconds on my laptop:

<Reveal this spoiler>

I have no idea if a shorter such program exists.

s''(q.S:$/9=(T1';s;(..)(..);$..=substr+crypt($1,$2),2,3;eg;print$..$/

In reply to Guess what it does ... and a challenge by liverpole

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