I've been looking for something short and sweet to put in my signature and I came up with this. It's not exactly an obfuscation, just a fairly dense bit of code. It prints something (IMO) more interesting than JAPH. 
/usr/bin/perl -le'X:for(my$x=1;;){$x%$_||next(X)for(2..$x++);print$x}'

[download]
It can use strict and warnings without further modification and it's only 70 columns wide, so it fits most places. What do you think?

In reply to small sig line by dbw

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