This was attempt to see if using format() would be shorter. It wasn't. It does use some of Perl's dustier artifacts however:

#!/usr/bin/perl -wall -00n
use strict;

END{
    @_=shift@F;
    while(@F){
        $_=shift @F;
        $_.=' '.shift@F while(length$_<=length$_[-1]&&@F);
        push@_,$_
    }
    formline(('@'.('|'x80)."\n")x@_,@_);
    print $^A
}
[download]

Update: Using MeowChow's regex this can be reduced to 89 chars + 6 command line switches. I'm not proud of this:

#!/usr/bin/perl -w -00nal
use strict;

END{
    $_="@F ";
    @F=1;
    formline'@'.('|'x80)."\n",$&and@F=length$&while/.{1,@F}.*? /g;
    print$^A
}
[download]

John.
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