diff --git a/CHANGELOG b/CHANGELOG.txt
similarity index 100%
rename from CHANGELOG
rename to CHANGELOG.txt
diff --git a/CREDITS b/CREDITS.txt
similarity index 98%
rename from CREDITS
rename to CREDITS.txt
index 3f491b7..fce3a5a 100644
--- a/CREDITS
+++ b/CREDITS.txt
@@ -98,5 +98,5 @@ Windows .rc file:
 Other stuff:
     Your name here! Patches go to icculus@icculus.org ...
 
-/* end of CREDITS ... */
+/* end of CREDITS.txt ... */
 
diff --git a/TODO b/TODO.txt
similarity index 99%
rename from TODO
rename to TODO.txt
index aa9d124..6b0ba74 100644
--- a/TODO
+++ b/TODO.txt
@@ -58,5 +58,5 @@ Stuff:
 - Make mutexes recursive, so callbacks can call into the API.
 - Archivers need abstracted i/o to read from memory or files (archives in archives?)
 
-// end of TODO ...
+// end of TODO.txt ...
 
diff --git a/physfs.h b/physfs.h
index 117dcbc..c40abb9 100644
--- a/physfs.h
+++ b/physfs.h
@@ -203,7 +203,7 @@
  * Please see the file LICENSE.txt in the source's root directory for licensing
  *  and redistribution rights.
  *
- * Please see the file CREDITS in the source's root directory for a more or
+ * Please see the file CREDITS.txt in the source's root directory for a more or
  *  less complete list of who's responsible for this.
  *
  *  \author Ryan C. Gordon.