diff --git a/src/bin/arcmutex.rs b/src/bin/arcmutex.rs
new file mode 100644
index 0000000..4643176
--- /dev/null
+++ b/src/bin/arcmutex.rs
@@ -0,0 +1,26 @@
+use std::sync::{Arc, Mutex};
+
+fn c<F: FnOnce() + 'static>(f: F) {
+    f();
+}
+
+fn main() {
+    let v = Arc::new(Mutex::new(vec![1, 2, 3]));
+
+    c({
+        let v = v.clone();
+        move || {
+            println!("inner 1: {:?}", v);
+            v.lock().unwrap().push(4);
+        }
+    });
+    c({
+        let v = v.clone();
+        move || {
+            println!("inner 2: {:?}", v);
+            v.lock().unwrap().push(5);
+        }
+    });
+
+    println!("outer: {:?}", v);
+}
diff --git a/src/bin/rcrefcell.rs b/src/bin/rcrefcell.rs
new file mode 100644
index 0000000..34271d2
--- /dev/null
+++ b/src/bin/rcrefcell.rs
@@ -0,0 +1,30 @@
+use std::{cell::RefCell, rc::Rc};
+
+fn c<F: FnOnce() + 'static>(f: F) {
+    f();
+}
+
+fn main() {
+    let v = Rc::new(RefCell::new(vec![1, 2, 3]));
+
+    c({
+        let v = v.clone();
+        move || {
+            println!("inner 1: {:?}", v);
+            v.replace_with(|old| {
+                old.push(4);
+                old.to_vec()
+            });
+        }
+    });
+    c({
+        let v = v.clone();
+        move || {
+            println!("inner 2: {:?}", v);
+            // This seems more readable than the example from https://www.youtube.com/watch?v=FTsaDmf0f_0 shown above
+            v.borrow_mut().push(5);
+        }
+    });
+
+    println!("outer: {:?}", v);
+}