diff --git a/.abCalcNDA.c.swp b/.abCalcNDA.c.swp
new file mode 100644
index 0000000..89477b2
Binary files /dev/null and b/.abCalcNDA.c.swp differ
diff --git a/ops/.abCOp.c.swp b/.abCalcNDA.defs.swp
similarity index 79%
rename from ops/.abCOp.c.swp
rename to .abCalcNDA.defs.swp
index 9dc7471..4ba1b75 100644
Binary files a/ops/.abCOp.c.swp and b/.abCalcNDA.defs.swp differ
diff --git a/.abCalcNDA.rez.swp b/.abCalcNDA.rez.swp
new file mode 100644
index 0000000..1f9dece
Binary files /dev/null and b/.abCalcNDA.rez.swp differ
diff --git a/Make.engine b/Make.engine
index 93eea13..e35e4c2 100644
--- a/Make.engine
+++ b/Make.engine
@@ -1,3 +1,9 @@
+#
+# Make.engine
+#    By: Jeremy Rand
+#
+
+
 CALC_OBJS=abCalc.o abCStack.o abCMode.o abCError.o
 
 EXPR_OBJS=expr/abCExpr.o expr/abCExpReal.o expr/abCExprInt.o
@@ -8,7 +14,9 @@ OPS_OBJS=ops/abCOp.o ops/abCOpAdd.o ops/abCOpSubtr.o ops/abCOpMult.o \
     ops/abCOpStws.o ops/abCOpRcws.o ops/abCOpSl.o ops/abCOpRl.o ops/abCOpSr.o \
     ops/abCOpRr.o ops/abCOpAsr.o
 
-OBJS=abCMain.o $(CALC_OBJS) $(EXPR_OBJS) $(OPS_OBJS)
+SHELL_OBJS=abCMain.o $(CALC_OBJS) $(EXPR_OBJS) $(OPS_OBJS)
+
+NDA_OBJS=abCNDA.o $(CALC_OBJS) $(EXPR_OBJS) $(OPS_OBJS)
 
 abCMain.o: abCalc.h abCStack.h expr/abCExpr.h ops/abCOp.h abCError.h
 
diff --git a/Make.mac b/Make.mac
index 343a9d0..26bdea8 100644
--- a/Make.mac
+++ b/Make.mac
@@ -1,3 +1,8 @@
+#
+# Make.mac
+#    By: Jeremy Rand
+#
+
 NAME=abCalc
 
 CFLAGS=-I.
@@ -6,8 +11,8 @@ all: $(NAME)
 
 include Make.engine
 
-$(NAME): $(OBJS)
-	cc -o $(NAME) $(OBJS)
+$(NAME): $(SHELL_OBJS)
+	cc -o $(NAME) $(SHELL_OBJS)
 
 clean:
-	rm -f $(NAME) $(OBJS)
+	rm -f $(NAME) $(SHELL_OBJS)
diff --git a/Makefile b/Makefile
index 27d4ad0..4382e0c 100644
--- a/Makefile
+++ b/Makefile
@@ -1,16 +1,26 @@
-NAME=abCalc
+#
+# Makefile
+#    By: Jeremy Rand
+#
 
-all: $(NAME)
+SHELL_NAME=abCalc
+NDA_NAME=abCalcNDA
+
+all: $(SHELL_NAME) $(NDA_NAME)
 
 .INCLUDE: "Make.engine"
 
 CFLAGS=-D ABCALC_GSOS
 
-$(NAME): fixtype $(OBJS)
-	occ -o $(NAME) $(OBJS)
+$(SHELL_NAME): fixtype $(SHELL_OBJS)
+	occ -o $(SHELL_NAME) $(SHELL_OBJS)
+
+$(NDA_NAME): fixtype $(NDA_OBJS)
+
 
 clean:
-	cp -p rm -f $(NAME) $(OBJS) $(NAME).r $(NAME).root
+	cp -p rm -f $(SHELL_NAME) $(SHELL_OBJS) $(SHELL_NAME).root
+	cp -p rm -f $(NDA_NAME) $(NDA_OBJS) $(NDA_NAME).r $(NDA_NAME).root
 	cp -p rm -f *.root
 	cp -p rm -f expr/*.root
 	cp -p rm -f ops/*.root
diff --git a/abCalcNDA.c b/abCalcNDA.c
new file mode 100644
index 0000000..9940b6f
--- /dev/null
+++ b/abCalcNDA.c
@@ -0,0 +1,73 @@
+/* 
+    abCalcNDA.c
+        By: Jeremy Rand
+ */
+
+
+#pragma nda NDAOpen NDAClose NDAAction NDAInit 60 0x03FF "  abCalc\\H**"
+
+
+#include <types.h>
+
+
+static BOOLEAN gCalcActive;
+static GrafPortPtr gCalcWinPtr;
+
+
+void NDAClose(void)
+{
+    if (gCalcActive) {
+        CloseWindow(gCalcWinPtr);
+        gCalcActive = FALSE;
+    }
+}
+
+
+void NDAInit(int code)
+{
+    if (code == 1)
+        gCalcActive = FALSE;
+    else if (gCalcActive)
+        NDAClose();
+}
+
+
+GrafPortPtr NDAOpen(void)
+{
+    GrafPortPtr wPtr;
+
+    wPtr = NULL;
+    if (!clockActive) {
+        if (OpenResourceFork()) {
+            gCalcWinPtr = NewWindow2("\p abCalc ", 0, NULL, NULL, 0x02, wrNum, rWindParam1);
+            if (toolerror() == 0) {
+                SetSysWindow(gCalcWinPtr);
+                clockActive = TRUE;
+                wPtr = clockWinPtr;
+            }
+            CloseResourceFork();
+        }
+    }
+    return wPtr;
+}
+
+
+BOOLEAN NDAAction(int code, EventRecord *sysEvent)
+{
+    int event;
+    static EventRecord localEvent;
+
+    switch (code) {
+        case eventAction:
+            localEvent.what = sysEvent->what;
+            localEvent.message = sysEvent->message;
+            localEvent.when = sysEvent->when;
+            localEvent.where = sysEvent->where;
+            localEvent.modifiers = sysEvent->modifiers;
+            event = TaskMasterDA(0, &localEvent);
+            break;
+        case runAction:
+            break;
+    }
+    return FALSE;
+}
diff --git a/abCalcNDA.defs b/abCalcNDA.defs
new file mode 100644
index 0000000..b60700d
--- /dev/null
+++ b/abCalcNDA.defs
@@ -0,0 +1,7 @@
+/* 
+    abCalcNDA.defs
+        By: Jeremy Rand
+ */
+
+#define ABCALC_WINDOW_NUM 1001
+#define ABCALC_LINED_COLORS 1002
diff --git a/abCalcNDA.rez b/abCalcNDA.rez
new file mode 100644
index 0000000..8492e0f
--- /dev/null
+++ b/abCalcNDA.rez
@@ -0,0 +1,37 @@
+/* 
+    abCalcNDA.h
+        By: Jeremy Rand
+ */
+
+
+#include "types.rez"
+#include "abCalcNda.defs"
+
+
+resource rWindParam1 (ABCALC_WINDOW_NUM) {
+   $C0A5,                      /* wFrameBits */
+   nil,                        /* wTitle */
+   0,                          /* wRefCon */
+   {0,0,0,0},                  /* ZoomRect */
+   ABCALC_LINED_COLORS,        /* wColor ID */
+   {0,0},                      /* Origin */
+   {0,0},                      /* data size */
+   {0,0},                      /* max height-width */
+   {0,0},                      /* scroll ver hors */
+   {0,0},                      /* page ver horiz */
+   0,                          /* winfoRefcon */
+   0,                          /* wInfoHeight */
+   {50,50,62,200},               /* wposition */
+   infront,                    /* wPlane */
+   nil,                        /* wStorage */
+   $0800                       /* wInVerb */
+   };
+
+
+resource rWindColor (ABCALC_LINED_COLORS) {
+   0x0000,                     /* frameColor */
+   0x0F00,                     /* titleColor */
+   0x020F,                     /* tbarColor */
+   0xF0F0,                     /* growColor */
+   0x00F0,                     /* infoColor */
+   };