diff --git a/IDEAS b/IDEAS
index 4b30c5c..b731e59 100644
--- a/IDEAS
+++ b/IDEAS
@@ -10,6 +10,10 @@ strategy. If not, then try to at least generalize it more.
 Try to create some more toggles on the indentation package, to make it at least
 a little bit configurable.
 
+Move some "global methods" which use particular modes into those modes' files.
+Also, try to combine some modes that are always intended to be used together
+(for instace, python/ipython, perl/iperl, */*mini, etc)  
+
 2009/03/27:
 
 1. Create a Method attribute meaning should-appear-in-help-buffers. Use this to
diff --git a/mode/diff.py b/mode/diff.py
index c4d69d8..733d477 100644
--- a/mode/diff.py
+++ b/mode/diff.py
@@ -1,14 +1,14 @@
 from mode import Fundamental
-from lex import Grammar, PatternRule
+from lex import Grammar, PatternRule, RegionRule, PatternMatchRule
 
 class DiffGrammar(Grammar):
     rules = [
-        PatternRule(name=r'left', pattern=r"^\-.*\n$"),
-        PatternRule(name=r'right', pattern=r"^\+.*\n$"),
-        PatternRule(name=r'metadata', pattern=r'^[A-Za-z].*\n$'),
-        PatternRule(name=r'seperator', pattern=r'^={67}\n$'),
-        PatternRule(name=r'location', pattern=r"^@@ [-+0-9a-z, ]* @@\n$"),
-        PatternRule(name=r'common', pattern=r"^.*\n$"),
+        PatternRule('diff.left', r"^\-.*\n$"),
+        PatternRule('diff.right', r"^\+.*\n$"),
+        PatternRule('diff.metadata', r'^[A-Za-z].*\n$'),
+        PatternRule('diff.seperator', r'^={67}\n$'),
+        PatternRule('diff.location', r"^@@ [-+0-9a-z, ]* @@\n$"),
+        PatternRule('diff.common', r"^.*\n$"),
     ]
 
 class Diff(Fundamental):
@@ -16,11 +16,37 @@ class Diff(Fundamental):
     extensions = ['.patch', '.diff']
     grammar    = DiffGrammar()
     colors     = {
-        'left':      ('red', 'default', 'bold'),
-        'right':     ('blue', 'default', 'bold'),
-        'seperator': ('magenta', 'default', 'bold'),
-        'metadata':  ('magenta', 'default', 'bold'),
-        'location':  ('magenta', 'default', 'bold'),
+        'diff.left':      ('red', 'default', 'bold'),
+        'diff.right':     ('blue', 'default', 'bold'),
+        'diff.seperator': ('magenta', 'default', 'bold'),
+        'diff.metadata':  ('magenta', 'default', 'bold'),
+        'diff.location':  ('magenta', 'default', 'bold'),
     }
 
-install = Diff.install
+class Diff3Line(Grammar):
+    rules = [PatternMatchRule('x', r'^(  )(.*)\n$', 'pre', 'data')]
+class Diff3Grammar(Grammar):
+    rules = [
+        PatternRule('diff.seperator', r'^====\n$'),
+        RegionRule('diff.part1', r"^1:\d+,\d+[a-z]\n$", Diff3Line, '^(?=[^ ])'),
+        RegionRule('diff.part2', r"^2:\d+,\d+[a-z]\n$", Diff3Line, '^(?=[^ ])'),
+        RegionRule('diff.part3', r"^3:\d+,\d+[a-z]\n$", Diff3Line, '^(?=[^ ])'),
+        PatternRule('diff.common', r"^.*\n$"),
+    ]
+
+class Diff3(Fundamental):
+    name       = 'diff3'
+    extensions = ['.diff3']
+    grammar    = Diff3Grammar()
+    colors     = {
+        'diff.part1.start': ('yellow', 'default', 'bold'),
+        'diff.part1.pre':   ('red', 'red', 'bold'),
+        'diff.part2.start': ('yellow', 'default', 'bold'),
+        'diff.part2.pre':   ('green', 'green', 'bold'),
+        'diff.part3.start': ('yellow', 'default', 'bold'),
+        'diff.part3.pre':   ('blue', 'blue', 'bold'),
+    }
+
+def install(*args, **kwargs):
+    Diff.install(*args, **kwargs)
+    Diff3.install(*args, **kwargs)