diff --git a/ChangeLog b/ChangeLog
index 8491624..90c84aa 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -2,6 +2,10 @@
 
 = Revision history for nuggets
 
+== 1.4.0 [unreleased]
+
+* Added File.open_file.
+
 == 1.3.0 [2015-07-07]
 
 * Added <tt>Hash.{identity,array}</tt>.
diff --git a/lib/nuggets/file/open_file.rb b/lib/nuggets/file/open_file.rb
new file mode 100644
index 0000000..01943d9
--- /dev/null
+++ b/lib/nuggets/file/open_file.rb
@@ -0,0 +1,5 @@
+require 'nuggets/file/open_file_mixin'
+
+class File
+  extend Nuggets::File::OpenFileMixin
+end
diff --git a/lib/nuggets/file/open_file_mixin.rb b/lib/nuggets/file/open_file_mixin.rb
new file mode 100644
index 0000000..e44c26f
--- /dev/null
+++ b/lib/nuggets/file/open_file_mixin.rb
@@ -0,0 +1,71 @@
+#--
+###############################################################################
+#                                                                             #
+# nuggets -- Extending Ruby                                                   #
+#                                                                             #
+# Copyright (C) 2007-2015 Jens Wille                                          #
+#                                                                             #
+# Authors:                                                                    #
+#     Jens Wille <jens.wille@gmail.com>                                       #
+#                                                                             #
+# nuggets is free software; you can redistribute it and/or modify it under    #
+# the terms of the GNU Affero General Public License as published by the Free #
+# Software Foundation; either version 3 of the License, or (at your option)   #
+# any later version.                                                          #
+#                                                                             #
+# nuggets is distributed in the hope that it will be useful, but WITHOUT ANY  #
+# WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS   #
+# FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for     #
+# more details.                                                               #
+#                                                                             #
+# You should have received a copy of the GNU Affero General Public License    #
+# along with nuggets. If not, see <http://www.gnu.org/licenses/>.             #
+#                                                                             #
+###############################################################################
+#++
+
+module Nuggets
+  class File
+    module OpenFileMixin
+
+  # call-seq:
+  #   File.open_file(filename[, options[, mode]]) -> anIO
+  #   File.open_file(filename[, options[, mode]]) { |io| ... } => anObject
+  #
+  # Supported options are +mode+ (defaults to +r+) and +encoding+ (defaults
+  # to the default external encoding).
+  #
+  # If +filename+ is +-+, sets +io+ to +STDOUT+ when in write mode or +STDIN+
+  # otherwise. Puts +io+ into binary mode if requested. Sets +io+'s encoding.
+  #
+  # If +filename+ ends with +.gz+ or +.gzip+, uses Zlib for reading or writing
+  # the file.
+  #
+  # Otherwise defers to ::open.
+  #
+  # Yields +io+ to the given block or returns it when no block given.
+  def open_file(filename, options = {}, mode = 'r', &block)
+    mode = options.fetch(:mode, mode); writing = mode =~ /w/
+
+    encoding = options.fetch(:encoding, ::Encoding.default_external)
+
+    case filename
+      when '-'
+        io = writing ? $stdout : $stdin
+        io.binmode if mode =~ /b/
+        io.set_encoding(encoding)
+
+        block ? block[io] : io
+      when /\.gz(?:ip)?\z/i
+        require 'zlib'
+
+        klass = writing ? ::Zlib::GzipWriter : ::Zlib::GzipReader
+        klass.open(filename, encoding: encoding, &block)
+      else
+        open(filename, mode, encoding: encoding, &block)
+    end
+  end
+
+    end
+  end
+end