Index: src/OFDictionary.h
==================================================================
--- src/OFDictionary.h
+++ src/OFDictionary.h
@@ -196,10 +196,24 @@
  * @return The object for the given key or `nil` if the key was not found
  */
 - (nullable ObjectType)objectForKey: (KeyType)key;
 - (nullable ObjectType)objectForKeyedSubscript: (KeyType)key;
 
+/*!
+ * @brief Returns the value for the given key or `nil` if the key was not
+ *	  found.
+ *
+ * If the key starts with an `@`, the `@` is stripped and
+ * `[super valueForKey:]` is called.
+ * If the key does not start with an `@`, this is equivalent to
+ * @ref objectForKey:.
+ *
+ * @param key The key whose value should be returned
+ * @return The value for the given key or `nil` if the key was not found
+ */
+- (nullable id)valueForKey: (OFString*)key;
+
 /*!
  * @brief Checks whether the dictionary contains an object equal to the
  *	  specified object.
  *
  * @param object The object which is checked for being in the dictionary

Index: src/OFDictionary.m
==================================================================
--- src/OFDictionary.m
+++ src/OFDictionary.m
@@ -277,10 +277,27 @@
 	OF_UNRECOGNIZED_SELECTOR
 }
 
 - (id)objectForKeyedSubscript: (id)key
 {
+	return [self objectForKey: key];
+}
+
+- (id)valueForKey: (OFString*)key
+{
+	if ([key hasPrefix: @"@"]) {
+		void *pool = objc_autoreleasePoolPush();
+		id ret;
+
+		key = [key substringWithRange: of_range(1, [key length] - 1)];
+		ret = [[super valueForKey: key] retain];
+
+		objc_autoreleasePoolPop(pool);
+
+		return [ret autorelease];
+	}
+
 	return [self objectForKey: key];
 }
 
 - (size_t)count
 {

Index: src/OFKeyValueCoding.h
==================================================================
--- src/OFKeyValueCoding.h
+++ src/OFKeyValueCoding.h
@@ -12,11 +12,15 @@
  * Public License, either version 2 or 3, which can be found in the file
  * LICENSE.GPLv2 or LICENSE.GPLv3 respectively included in the packaging of this
  * file.
  */
 
+#import "macros.h"
+
 @class OFString;
+
+OF_ASSUME_NONNULL_BEGIN
 
 /*!
  * @protocol OFKeyValueCoding OFKeyValueCoding.h ObjFW/OFKeyValueCoding.h
  *
  * @brief A protocol for Key Value Coding.
@@ -29,11 +33,11 @@
  * @brief Return the value for the specified key
  *
  * @param key The key of the value to return
  * @return The value for the specified key
  */
-- (id)valueForKey: (OFString*)key;
+- (nullable id)valueForKey: (OFString*)key;
 
 /*!
  * @brief This is called by @ref valueForKey: if the specified key does not
  *	  exist.
  *
@@ -40,19 +44,19 @@
  * By default, this throws an @ref OFUndefinedKeyException.
  *
  * @param key The undefined key of the value to return
  * @return The value for the specified undefined key
  */
-- (id)valueForUndefinedKey: (OFString*)key;
+- (nullable id)valueForUndefinedKey: (OFString*)key;
 
 /*!
  * @brief Set the value for the specified key
  *
  * @param value The value for the specified key
  * @param key The key of the value to set
  */
-- (void)setValue: (id)value
+- (void)setValue: (nullable id)value
 	  forKey: (OFString*)key;
 
 /*!
  * @brief This is called by @ref setValue:forKey: if the specified key does not
  *	  exist.
@@ -60,8 +64,10 @@
  * By default, this throws an @ref OFUndefinedKeyException.
  *
  * @param value The value for the specified undefined key
  * @param key The undefined key of the value to set
  */
--  (void)setValue: (id)value
+-  (void)setValue: (nullable id)value
   forUndefinedKey: (OFString*)key;
 @end
+
+OF_ASSUME_NONNULL_END

Index: src/OFMutableDictionary.h
==================================================================
--- src/OFMutableDictionary.h
+++ src/OFMutableDictionary.h
@@ -75,10 +75,24 @@
 - (void)setObject: (ObjectType)object
 	   forKey: (KeyType)key;
 -   (void)setObject: (ObjectType)object
   forKeyedSubscript: (KeyType)key;
 
+/*!
+ * @brief Sets a value for a key.
+ *
+ * If the key starts with an `@`, the `@` is stripped and
+ * `[super setValue:forKey:]` is called.
+ * If the key does not start with an `@`, this is equivalent to
+ * @ref setObject:forKey:.
+ *
+ * @param key The key to set
+ * @param value The value to set the key to
+ */
+- (void)setValue: (nullable id)value
+	  forKey: (OFString*)key;
+
 /*!
  * @brief Removes the object for the specified key from the dictionary.
  *
  * @param key The key whose object should be removed
  */

Index: src/OFMutableDictionary.m
==================================================================
--- src/OFMutableDictionary.m
+++ src/OFMutableDictionary.m
@@ -18,10 +18,11 @@
 
 #include <stdlib.h>
 
 #import "OFMutableDictionary_hashtable.h"
 #import "OFArray.h"
+#import "OFString.h"
 
 static struct {
 	Class isa;
 } placeholder;
 
@@ -173,10 +174,28 @@
   forKeyedSubscript: (id)key
 {
 	[self setObject: object
 		 forKey: key];
 }
+
+- (void)setValue: (id)value
+	  forKey: (OFString*)key
+{
+	if ([key hasPrefix: @"@"]) {
+		void *pool = objc_autoreleasePoolPush();
+
+		key = [key substringWithRange: of_range(1, [key length] - 1)];
+		[super setValue: value
+			 forKey: key];
+
+		objc_autoreleasePoolPop(pool);
+		return;
+	}
+
+	[self setObject: value
+		 forKey: key];
+}
 
 - (void)removeObjectForKey: (id)key
 {
 	OF_UNRECOGNIZED_SELECTOR
 }

Index: tests/OFDictionaryTests.m
==================================================================
--- tests/OFDictionaryTests.m
+++ tests/OFDictionaryTests.m
@@ -17,10 +17,11 @@
 #include "config.h"
 
 #import "OFDictionary.h"
 #import "OFString.h"
 #import "OFArray.h"
+#import "OFNumber.h"
 #import "OFAutoreleasePool.h"
 
 #import "OFEnumerationMutationException.h"
 
 #import "TestsAppDelegate.h"
@@ -44,18 +45,23 @@
 	OFEnumerator *key_enum, *obj_enum;
 	OFArray *akeys, *avalues;
 
 	[dict setObject: values[0]
 		 forKey: keys[0]];
-	[dict setObject: values[1]
-		 forKey: keys[1]];
+	[dict setValue: values[1]
+		forKey: keys[1]];
 
 	TEST(@"-[objectForKey:]",
 	    [[dict objectForKey: keys[0]] isEqual: values[0]] &&
 	    [[dict objectForKey: keys[1]] isEqual: values[1]] &&
 	    [dict objectForKey: @"key3"] == nil)
 
+	TEST(@"-[valueForKey:]",
+	    [[dict valueForKey: keys[0]] isEqual: values[0]] &&
+	    [[dict valueForKey: @"@count"] isEqual:
+	    [OFNumber numberWithSize: 2]])
+
 	TEST(@"-[containsObject:]",
 	    [dict containsObject: values[0]] &&
 	    ![dict containsObject: @"nonexistant"])
 
 	TEST(@"-[containsObjectIdenticalTo:]",