diff --git a/Makefile b/Makefile
index d67ced2b..7481dcf6 100644
--- a/Makefile
+++ b/Makefile
@@ -1,9 +1,13 @@
 default: help
 
 help:
-	@echo "minify  - makes JavaScript download and run faster"
-	@echo "lint    - checks JavaScript files for style issues"
-	@echo "test    - runs JavaScript unit tests"
+	@echo "minify         - makes JavaScript download and run faster"
+	@echo "lint           - checks JavaScript files for style issues"
+	@echo "test           - runs JavaScript unit tests"
+	@echo "ext-chr-gmail  - creates the Google Chrome / Google Mail extension"
+
+ext-chr-gmail:
+	@./scripts/create_extension.sh
 
 lint:
 	@echo See http://code.google.com/closure/utilities/
diff --git a/scripts/create_extension.sh b/scripts/create_extension.sh
new file mode 100755
index 00000000..8d5a34cf
--- /dev/null
+++ b/scripts/create_extension.sh
@@ -0,0 +1,27 @@
+#!/bin/bash
+################################################################################
+# OpenPGP.js browser extension build script
+#
+# @author   Alex
+################################################################################
+
+echo "Setup..."
+dir_extension="plugins/chrome/"
+dir_webcode="webmail/googlemail.com/"
+dir_target="`mktemp -d browserext.XXX`"
+dir_build="build/";
+sh_pack="./scripts/pack.sh"
+file_key="resources/openpgpjs.pem"
+file_extension="build/openpgpjs.crx"
+mkdir -p "$dir_build"
+
+echo "Copying files..."
+cp -R "$dir_extension"/* "$dir_target"
+cp -R "$dir_webcode"/* "$dir_target"
+
+echo "Creating extension..."
+$sh_pack "$dir_target" "$file_key"
+
+echo "Cleaning up..."
+rm -rf "$dir_target"
+mv "$dir_target".crx "$file_extension"
diff --git a/scripts/pack.sh b/scripts/pack.sh
new file mode 100755
index 00000000..76db149c
--- /dev/null
+++ b/scripts/pack.sh
@@ -0,0 +1,44 @@
+#!/bin/bash -e
+#
+# Purpose: Pack a Chromium extension directory into crx format
+
+if test $# -ne 2; then
+  echo "Usage: crxmake.sh <extension dir> <pem path>"
+  exit 1
+fi
+
+dir=$1
+key=$2
+name=$(basename "$dir")
+crx="$name.crx"
+pub="$name.pub"
+sig="$name.sig"
+zip="$name.zip"
+trap 'rm -f "$pub" "$sig" "$zip"' EXIT
+
+# zip up the crx dir
+cwd=$(pwd -P)
+(cd "$dir" && zip -qr -9 -X "$cwd/$zip" .)
+
+# signature
+openssl sha1 -sha1 -binary -sign "$key" < "$zip" > "$sig"
+
+# public key
+openssl rsa -pubout -outform DER < "$key" > "$pub" 2>/dev/null
+
+byte_swap () {
+  # Take "abcdefgh" and return it as "ghefcdab"
+  echo "${1:6:2}${1:4:2}${1:2:2}${1:0:2}"
+}
+
+crmagic_hex="4372 3234" # Cr24
+version_hex="0200 0000" # 2
+pub_len_hex=$(byte_swap $(printf '%08x\n' $(ls -l "$pub" | awk '{print $5}')))
+sig_len_hex=$(byte_swap $(printf '%08x\n' $(ls -l "$sig" | awk '{print $5}')))
+(
+  echo "$crmagic_hex $version_hex $pub_len_hex $sig_len_hex" | xxd -r -p
+  cat "$pub" "$sig" "$zip"
+) > "$crx"
+echo "Wrote $crx"
+
+exit 0