A co-worker of mine has 600,000+ .EML files which contain some UTF-8 encoded text. Here's a sample: 
To: =?utf-8?B?Q2FuY2VsbGF0aW9uIDxDYW5jZWxsYXRpb25Abm9ydmVyZ2VuY2UuY29t
+Pg==?=
CC: =?utf-8?B?VGltIEhpbGtlIChSVlApIDx0aW0uaGlsa2VAbm9ydmVyZ2VuY2UuY29t
+PiwgQmVybmFyZCBDb3lsZSBNVlAgb2
YgREMgPGJlcm5hcmQuY295bGVAbm9ydmVyZ2VuY2UuY29tPiwgRGF2aWQgQnV0bGVyIChB
+VlApIDxkYXZpZC5idXRsZXJAbm9ydm
VyZ2VuY2UuY29tPiwgVGltb3RoeSBDYXNleSA8dGltb3RoeS5jYXNleUBub3J2ZXJnZW5j
+ZS5jb20+?=
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Subject: SOME EMAIL SUBJECT
Date: Thu, 24 Jun 2004 13:47:44 -0400
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[download]
He'd like to decode the To: and Cc: lines. What tools are necessary to do this?
Update: Upon examining MIME::Parser, I've tracked down the necessary code in MIME::Words. My solution is:
#!/usr/bin/perl

use MIME::Words 'decode_mimewords';
use strict;
use warnings;

my @files = @ARGV;

for my $file (@files) {
  local @ARGV = ($file);
  local $^I = ".bak";
  local $/;

  print scalar decode_mimewords($_) while <>;
}

[download]
Jeff japhy Pinyan, P.L., P.M., P.O.D, X.S.: Perl, regex, and perl hacker
How can we ever be the sold short or the cheated, we who for every service have long ago been overpaid? ~~ Meister Eckhart

In reply to Decoding UTF-8 charset in an .EML file by japhy

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