diff --git a/bumblebee/modules/disk.py b/bumblebee/modules/disk.py
new file mode 100644
index 0000000..586909f
--- /dev/null
+++ b/bumblebee/modules/disk.py
@@ -0,0 +1,50 @@
+# pylint: disable=C0111,R0903
+
+"""Shows free diskspace, total diskspace and the percentage of free disk space.
+
+Parameters:
+    * disk.warning: Warning threshold in % of disk space (defaults to 80%)
+    * disk.critical: Critical threshold in % of disk space (defaults ot 90%)
+    * disk.path: Path to calculate disk usage from (defaults to /)
+"""
+
+import os
+
+import bumblebee.input
+import bumblebee.output
+import bumblebee.engine
+
+class Module(bumblebee.engine.Module):
+    def __init__(self, engine, config):
+        super(Module, self).__init__(engine, config,
+            bumblebee.output.Widget(full_text=self.diskspace)
+        )
+        self._path = self.parameter("path", "/")
+        self._perc = 0
+
+        engine.input.register_callback(self, button=bumblebee.input.LEFT_MOUSE,
+            cmd="nautilus {}".format(self._path))
+
+    def diskspace(self):
+        st = os.statvfs(self._path)
+        size = st.f_frsize*st.f_blocks
+        used = size - st.f_frsize*st.f_bavail
+        self._perc = 100.0*used/size
+
+        return "{} {}/{} ({:05.02f}%)".format(self._path,
+            bumblebee.util.bytefmt(used),
+            bumblebee.util.bytefmt(size), self._perc
+        )
+
+    def update(self, widgets):
+        pass
+
+    def state(self, widget):
+        pass
+    def warning(self, widget):
+        return self._perc > self._config.parameter("warning", 80)
+
+    def critical(self, widget):
+        return self._perc > self._config.parameter("critical", 90)
+
+# vim: tabstop=8 expandtab shiftwidth=4 softtabstop=4
diff --git a/bumblebee/util.py b/bumblebee/util.py
index 24e2cb1..f35ce89 100644
--- a/bumblebee/util.py
+++ b/bumblebee/util.py
@@ -18,6 +18,13 @@ def execute(cmd, wait=True):
         return out.decode("utf-8")
     return None
 
+def bytefmt(num):
+    for unit in [ "", "Ki", "Mi", "Gi" ]:
+        if num < 1024.0:
+            return "{:.2f}{}B".format(num, unit)
+        num /= 1024.0
+    return "{:05.2f%}{}GiB".format(num)
+
 def durationfmt(duration):
     minutes, seconds = divmod(duration, 60)
     hours, minutes = divmod(minutes, 60)
diff --git a/tests/modules/test_disk.py b/tests/modules/test_disk.py
new file mode 100644
index 0000000..3ee74b0
--- /dev/null
+++ b/tests/modules/test_disk.py
@@ -0,0 +1,36 @@
+# pylint: disable=C0103,C0111
+
+import json
+import unittest
+import mock
+
+import bumblebee.input
+from bumblebee.input import I3BarInput
+from bumblebee.modules.disk import Module
+from tests.util import MockEngine, MockConfig, assertPopen
+
+class TestDiskModule(unittest.TestCase):
+    def setUp(self):
+        self.engine = MockEngine()
+        self.engine.input = I3BarInput()
+        self.engine.input.need_event = True
+        self.config = MockConfig()
+        self.config.set("disk.path", "somepath")
+        self.module = Module(engine=self.engine, config={"config": self.config})
+
+    @mock.patch("select.select")
+    @mock.patch("subprocess.Popen")
+    @mock.patch("sys.stdin")
+    def test_leftclick(self, mock_input, mock_output, mock_select):
+        mock_input.readline.return_value = json.dumps({
+            "name": self.module.id,
+            "button": bumblebee.input.LEFT_MOUSE,
+            "instance": None
+        })
+        mock_select.return_value = (1,2,3)
+        self.engine.input.start()
+        self.engine.input.stop()
+        mock_input.readline.assert_any_call()
+        assertPopen(mock_output, "nautilus {}".format(self.module.parameter("path")))
+
+# vim: tabstop=8 expandtab shiftwidth=4 softtabstop=4