diff -up dwm-5.8.2/config.def.h dwm-5.8.2-swap/config.def.h
--- dwm-5.8.2/config.def.h	2010-06-04 13:39:15.000000000 +0300
+++ dwm-5.8.2-swap/config.def.h	2011-01-26 07:53:44.607195598 +0200
@@ -53,6 +53,7 @@ static Key keys[] = {
 	{ MODKEY,                       XK_p,      spawn,          {.v = dmenucmd } },
 	{ MODKEY|ShiftMask,             XK_Return, spawn,          {.v = termcmd } },
 	{ MODKEY,                       XK_b,      togglebar,      {0} },
+	{ MODKEY,                       XK_s,      swapfocus,      {0} },
 	{ MODKEY,                       XK_j,      focusstack,     {.i = +1 } },
 	{ MODKEY,                       XK_k,      focusstack,     {.i = -1 } },
 	{ MODKEY,                       XK_h,      setmfact,       {.f = -0.05} },
Only in dwm-5.8.2-swap: config.h
diff -up dwm-5.8.2/dwm.c dwm-5.8.2-swap/dwm.c
--- dwm-5.8.2/dwm.c	2010-06-04 13:39:15.000000000 +0300
+++ dwm-5.8.2-swap/dwm.c	2011-01-26 07:54:27.741193905 +0200
@@ -183,6 +183,7 @@ static void focus(Client *c);
 static void focusin(XEvent *e);
 static void focusmon(const Arg *arg);
 static void focusstack(const Arg *arg);
+static void swapfocus();
 static unsigned long getcolor(const char *colstr);
 static Bool getrootptr(int *x, int *y);
 static long getstate(Window w);
@@ -244,6 +245,7 @@ static int xerrorstart(Display *dpy, XEr
 static void zoom(const Arg *arg);
 
 /* variables */
+static Arg focusdirection={.i=1};
 static const char broken[] = "broken";
 static char stext[256];
 static int screen;
@@ -862,6 +864,8 @@ focusmon(const Arg *arg) {
 
 void
 focusstack(const Arg *arg) {
+	focusdirection.i=arg->i;
+	
 	Client *c = NULL, *i;
 
 	if(!selmon->sel)
@@ -886,6 +890,13 @@ focusstack(const Arg *arg) {
 	}
 }
 
+void 
+swapfocus(){
+	focusdirection.i*=-1;
+	focusstack(&focusdirection);
+}
+
+
 unsigned long
 getcolor(const char *colstr) {
 	Colormap cmap = DefaultColormap(dpy, screen);