diff --git a/src/micropolisj/build_tool/RearrangeTiles.java b/src/micropolisj/build_tool/RearrangeTiles.java
new file mode 100644
index 0000000..513b872
--- /dev/null
+++ b/src/micropolisj/build_tool/RearrangeTiles.java
@@ -0,0 +1,56 @@
+package micropolisj.build_tool;
+
+import java.awt.*;
+import java.awt.image.BufferedImage;
+import java.io.*;
+import java.util.*;
+import javax.imageio.*;
+import javax.swing.ImageIcon;
+
+/**
+ * Just a little utility I wrote to rearrange 16x16 tiles into a grid
+ * of a different width. Not included in the Micropolis build.
+ */
+public class RearrangeTiles
+{
+	static final int DEST_COLUMNS = 16;
+	static final int TILE_SIZE = 16;
+
+	public static void main(String [] args)
+		throws Exception
+	{
+		File inputFile = new File(args[0]);
+		File outputFile = new File(args[1]);
+
+		// read in the image
+		Image srcImage = new ImageIcon(inputFile.toString()).getImage();
+		int srcCols = srcImage.getWidth(null) / TILE_SIZE;
+		int srcRows = srcImage.getHeight(null) / TILE_SIZE;
+		int ntiles = srcRows * srcCols;
+
+		// actually assemble the image
+		int destCols = DEST_COLUMNS;
+		int destRows = (ntiles + destCols-1) / destCols;
+		BufferedImage buf = new BufferedImage(TILE_SIZE*DEST_COLUMNS,TILE_SIZE*destRows,BufferedImage.TYPE_INT_RGB);
+		Graphics2D gr = buf.createGraphics();
+
+		for (int i = 0; i < ntiles; i++) {
+
+			int srcRow = i / srcCols;
+			int srcCol = i % srcCols;
+
+			int destRow = i / destCols;
+			int destCol = i % destCols;
+
+			gr.drawImage(
+				srcImage,
+				destCol*TILE_SIZE, destRow*TILE_SIZE,
+				(destCol+1)*TILE_SIZE,(destRow+1)*TILE_SIZE,
+				srcCol*TILE_SIZE, srcRow*TILE_SIZE,
+				(srcCol+1)*TILE_SIZE, (srcRow+1)*TILE_SIZE,
+				null);
+		}
+
+		ImageIO.write(buf, "png", outputFile);
+	}
+}