diff -r 5f851f669a15 -r 3e372ded7adc minesweeper/src/main/java/org/apidesign/demo/minesweeper/MinesModel.java
--- a/minesweeper/src/main/java/org/apidesign/demo/minesweeper/MinesModel.java	Fri Feb 07 21:36:27 2014 +0100
+++ b/minesweeper/src/main/java/org/apidesign/demo/minesweeper/MinesModel.java	Sat Feb 08 06:23:40 2014 +0100
@@ -54,12 +54,13 @@
         @Property(name = "mine", type = boolean.class)
     })
     static class SquareModel {
-        @ComputedProperty static String text(SquareType state) {
+        @ComputedProperty static String html(SquareType state) {
             if (state == null) return " ";
             switch (state) {
                 case EXPLOSION: return "B";
                 case UNKNOWN: return "?";
-                case N_0: return " ";
+                case DISCOVERED: return "✔";  
+                case N_0: return " ";
             }
             return "" + state.ordinal();
         }