diff --git a/compressor/tests/precompiler.py b/compressor/tests/precompiler.py
index 6cc185a..9c2ac13 100644
--- a/compressor/tests/precompiler.py
+++ b/compressor/tests/precompiler.py
@@ -1,17 +1,33 @@
 #!/usr/bin/env python
 import optparse
+import sys
 
 def main():
     p = optparse.OptionParser()
+    p.add_option('-f', '--file', action="store", 
+                type="string", dest="filename", 
+                help="File to read from, defaults to stdin", default=None)
+    p.add_option('-o', '--output', action="store",
+                type="string", dest="outfile", 
+                help="File to write to, defaults to stdout", default=None)
+                
     options, arguments = p.parse_args()
     
-    f = open(arguments[0])
-    content = f.read()
-    f.close()
+    if options.filename:
+        f = open(options.filename)
+        content = f.read()
+        f.close()
+    else:
+        content = sys.stdin.read()
     
-    f = open(arguments[1], 'w')
-    f.write(content.replace('background:', 'color:'))
-    f.close()
+    content = content.replace('background:', 'color:')
+    
+    if options.outfile:
+        f = open(options.outfile, 'w')
+        f.write(content)
+        f.close()
+    else:
+        print content
 
  
 if __name__ == '__main__':
diff --git a/compressor/tests/tests.py b/compressor/tests/tests.py
index afa0eaa..324fb55 100644
--- a/compressor/tests/tests.py
+++ b/compressor/tests/tests.py
@@ -485,13 +485,35 @@ CssTidyTestCase = skipIf(
 class PrecompilerTestCase(TestCase):
     
     def setUp(self):
-        self.command = 'python %s/precompiler.py {infile} {outfile}' % os.path.dirname(__file__)
         self.filename = os.path.join(os.path.dirname(__file__), 'media/css/one.css')
         f = open(self.filename, 'r')
         self.content = f.read()
         f.close()
 
-    def test_precompiler(self):
+    def test_precompiler_infile_outfile(self):
         from compressor.filters.base import CompilerFilter
-        output = CompilerFilter(content=self.content, filename=self.filename, command=self.command).output()
+        command = 'python %s/precompiler.py -f {infile} -o {outfile}' % os.path.dirname(__file__)
+        output = CompilerFilter(content=self.content, filename=self.filename, command=command).output()
         self.assertEqual(u"body { color:#990; }", output)
+        
+    def test_precompiler_stdin_outfile(self):
+        from compressor.filters.base import CompilerFilter
+        command = 'python %s/precompiler.py -o {outfile}' % os.path.dirname(__file__)
+        output = CompilerFilter(content=self.content, filename=None, command=command).output()
+        self.assertEqual(u"body { color:#990; }", output)
+        
+    def test_precompiler_stdin_stdout(self):
+        from compressor.filters.base import CompilerFilter
+        command = 'python %s/precompiler.py' % os.path.dirname(__file__)
+        output = CompilerFilter(content=self.content, filename=None, command=command).output()
+        self.assertEqual(u"body { color:#990; }\n", output)
+        
+    def test_precompiler_infile_stdout(self):
+        from compressor.filters.base import CompilerFilter
+        command = 'python %s/precompiler.py -f {infile}' % os.path.dirname(__file__)
+        output = CompilerFilter(content=self.content, filename=None, command=command).output()
+        self.assertEqual(u"body { color:#990; }\n", output)
+        
+        
+        
+