diff --git a/insane.py b/insane.py
new file mode 100644
index 0000000..a89d14a
--- /dev/null
+++ b/insane.py
@@ -0,0 +1,50 @@
+import os
+import email
+
+from io import BytesIO, StringIO
+from email.generator import Generator
+
+import emailtunnel
+
+
+def main():
+    for filename in sorted(os.listdir('insane')):
+        if filename.endswith('.in'):
+            with open('insane/%s' % filename, 'rb') as fp:
+                a = fp.read()
+            if a.startswith(b'From nobody'):
+                nl = a.index(b'\n')
+                a = a[nl+1:]
+                strip_from = True
+            else:
+                strip_from = False
+            message = email.message_from_string(a)
+
+            fp = BytesIO()
+            g = Generator(fp,
+                          mangle_from_=False,
+                          maxheaderlen=0)
+            g.flatten(message, unixfrom=False)
+            b = fp.getvalue()
+
+            a = a.rstrip(b'\n')
+            b = b.rstrip(b'\n')
+
+            a_s = emailtunnel.Message.sanity_strip(a)
+            b_s = emailtunnel.Message.sanity_strip(b)
+
+            after_stripping = ' after stripping From' if strip_from else ''
+            if a == b:
+                print("%s: OK -- identical%s" % (filename, after_stripping))
+            elif a_s == b_s:
+                print("%s: OK%s" % (filename, after_stripping))
+            elif len(a_s) != len(b_s):
+                print("%s: Different # lines" % (filename,))
+                o = next((i, al, bl) for i, (al, bl) in enumerate(zip(a_s, b_s)) if al != bl)
+                print(o)
+            else:
+                print("%s: Not OK" % (filename,))
+
+
+if __name__ == "__main__":
+    main()