diff --git a/range.cpp b/range.cpp
index 55b8d763..3e70aa82 100644
--- a/range.cpp
+++ b/range.cpp
@@ -95,6 +95,23 @@ range<T>::normalise (T val) const {
 }
 
 
+template <typename T>
+range<T>&
+range<T>::operator*= (T val) {
+    min *= val;
+    max *= val;
+
+    return *this;
+}
+
+
+template <typename T>
+range<T>
+range<T>::operator* (T val) const {
+    return range<T> (min * val, max * val);
+}
+
+
 namespace util {
     template <>
     double
diff --git a/range.hpp b/range.hpp
index 3a809f1f..4c76e99e 100644
--- a/range.hpp
+++ b/range.hpp
@@ -48,9 +48,22 @@ namespace util {
 
         /// Expand the range to include this value if necessary
         void expand (T val);
+
         /// Normalise a number to [0, 1] within the range. Does not check bounds.
         double normalise (T val) const;
 
+        range& operator*= (T);
+        range  operator*  (T) const;
+
+        range& operator/= (T);
+        range  operator/  (T) const;
+
+        range& operator+= (T);
+        range  operator+  (T) const;
+
+        range& operator-= (T);
+        range  operator-  (T) const;
+
         /// Return a pseudo-random uniformly distributed value within the range.
         /// There are no statistical randomness guarantees whatsoever. 
         T random (void) const;