diff --git a/extra/24-game/tags.txt b/extra/24-game/tags.txt
new file mode 100644
index 0000000000..cb5fc203e1
--- /dev/null
+++ b/extra/24-game/tags.txt
@@ -0,0 +1 @@
+demos
diff --git a/extra/bubble-chamber/tags.txt b/extra/bubble-chamber/tags.txt
new file mode 100644
index 0000000000..cb5fc203e1
--- /dev/null
+++ b/extra/bubble-chamber/tags.txt
@@ -0,0 +1 @@
+demos
diff --git a/extra/cfdg/models/aqua-star/tags.txt b/extra/cfdg/models/aqua-star/tags.txt
new file mode 100644
index 0000000000..cb5fc203e1
--- /dev/null
+++ b/extra/cfdg/models/aqua-star/tags.txt
@@ -0,0 +1 @@
+demos
diff --git a/extra/cfdg/models/chiaroscuro/tags.txt b/extra/cfdg/models/chiaroscuro/tags.txt
new file mode 100644
index 0000000000..cb5fc203e1
--- /dev/null
+++ b/extra/cfdg/models/chiaroscuro/tags.txt
@@ -0,0 +1 @@
+demos
diff --git a/extra/cfdg/models/flower6/tags.txt b/extra/cfdg/models/flower6/tags.txt
new file mode 100644
index 0000000000..cb5fc203e1
--- /dev/null
+++ b/extra/cfdg/models/flower6/tags.txt
@@ -0,0 +1 @@
+demos
diff --git a/extra/cfdg/models/game1-turn6/tags.txt b/extra/cfdg/models/game1-turn6/tags.txt
new file mode 100644
index 0000000000..cb5fc203e1
--- /dev/null
+++ b/extra/cfdg/models/game1-turn6/tags.txt
@@ -0,0 +1 @@
+demos
diff --git a/extra/cfdg/models/lesson/tags.txt b/extra/cfdg/models/lesson/tags.txt
new file mode 100644
index 0000000000..cb5fc203e1
--- /dev/null
+++ b/extra/cfdg/models/lesson/tags.txt
@@ -0,0 +1 @@
+demos
diff --git a/extra/cfdg/models/rules08/tags.txt b/extra/cfdg/models/rules08/tags.txt
new file mode 100644
index 0000000000..cb5fc203e1
--- /dev/null
+++ b/extra/cfdg/models/rules08/tags.txt
@@ -0,0 +1 @@
+demos
diff --git a/extra/cfdg/models/sierpinski/tags.txt b/extra/cfdg/models/sierpinski/tags.txt
new file mode 100644
index 0000000000..cb5fc203e1
--- /dev/null
+++ b/extra/cfdg/models/sierpinski/tags.txt
@@ -0,0 +1 @@
+demos
diff --git a/extra/cfdg/models/snowflake/tags.txt b/extra/cfdg/models/snowflake/tags.txt
new file mode 100644
index 0000000000..cb5fc203e1
--- /dev/null
+++ b/extra/cfdg/models/snowflake/tags.txt
@@ -0,0 +1 @@
+demos
diff --git a/extra/lsys/ui/tags.txt b/extra/lsys/ui/tags.txt
new file mode 100644
index 0000000000..cb5fc203e1
--- /dev/null
+++ b/extra/lsys/ui/tags.txt
@@ -0,0 +1 @@
+demos
diff --git a/extra/springies/models/2snake/tags.txt b/extra/springies/models/2snake/tags.txt
new file mode 100644
index 0000000000..cb5fc203e1
--- /dev/null
+++ b/extra/springies/models/2snake/tags.txt
@@ -0,0 +1 @@
+demos
diff --git a/extra/springies/models/2x2snake/tags.txt b/extra/springies/models/2x2snake/tags.txt
new file mode 100644
index 0000000000..cb5fc203e1
--- /dev/null
+++ b/extra/springies/models/2x2snake/tags.txt
@@ -0,0 +1 @@
+demos
diff --git a/extra/springies/models/3snake/tags.txt b/extra/springies/models/3snake/tags.txt
new file mode 100644
index 0000000000..cb5fc203e1
--- /dev/null
+++ b/extra/springies/models/3snake/tags.txt
@@ -0,0 +1 @@
+demos
diff --git a/extra/springies/models/ball/tags.txt b/extra/springies/models/ball/tags.txt
new file mode 100644
index 0000000000..cb5fc203e1
--- /dev/null
+++ b/extra/springies/models/ball/tags.txt
@@ -0,0 +1 @@
+demos
diff --git a/extra/springies/models/belt-tire/tags.txt b/extra/springies/models/belt-tire/tags.txt
new file mode 100644
index 0000000000..cb5fc203e1
--- /dev/null
+++ b/extra/springies/models/belt-tire/tags.txt
@@ -0,0 +1 @@
+demos
diff --git a/extra/springies/models/nifty/tags.txt b/extra/springies/models/nifty/tags.txt
new file mode 100644
index 0000000000..cb5fc203e1
--- /dev/null
+++ b/extra/springies/models/nifty/tags.txt
@@ -0,0 +1 @@
+demos
diff --git a/extra/springies/models/urchin/tags.txt b/extra/springies/models/urchin/tags.txt
new file mode 100644
index 0000000000..cb5fc203e1
--- /dev/null
+++ b/extra/springies/models/urchin/tags.txt
@@ -0,0 +1 @@
+demos