diff --git a/code/_compile_options.dm b/code/_compile_options.dm
index adebd47b98c..6b6ce01d996 100644
--- a/code/_compile_options.dm
+++ b/code/_compile_options.dm
@@ -5,6 +5,11 @@
 								//By using the testing("message") proc you can create debug-feedback for people with this
 								//uncommented, but not visible in the release version)
 
+#define PRELOAD_RSC	1			/*set to:
+								0 to allow using external resources or on-demand behaviour;
+								1 to use the default behaviour;
+								2 for preloading absolutely everything;
+								*/
 
 
 //SYSTEM TOGGLES - these allow you to compile the game without some of the laggier systems if your server cannot cope with demand
diff --git a/code/modules/client/client defines.dm b/code/modules/client/client defines.dm
index 3ef743c60b8..3c1dd2ccb6f 100644
--- a/code/modules/client/client defines.dm	
+++ b/code/modules/client/client defines.dm	
@@ -37,3 +37,5 @@
 	var/player_age = "Requires database"	//So admins know why it isn't working - Used to determine how old the account is - in days.
 	var/related_accounts_ip = "Requires database"	//So admins know why it isn't working - Used to determine what other accounts previously logged in from this ip
 	var/related_accounts_cid = "Requires database"	//So admins know why it isn't working - Used to determine what other accounts previously logged in from this computer id
+
+	preload_rsc = PRELOAD_RSC
diff --git a/code/modules/client/client procs.dm b/code/modules/client/client procs.dm
index adef2c387cc..6009a644d7a 100644
--- a/code/modules/client/client procs.dm	
+++ b/code/modules/client/client procs.dm	
@@ -46,6 +46,12 @@
 
 	..()	//redirect to hsrc.Topic()
 
+/client/proc/is_content_unlocked()
+	if(!prefs.unlock_content)
+		src << "Become a BYOND member to access member-perks and features, as well as support the engine that makes this game possible. <a href='http://www.byond.com/membership'>Click Here to find out more</a>."
+		return 0
+	return 1
+
 /client/proc/handle_spam_prevention(var/message, var/mute_type)
 	if(config.automute_on && !holder && src.last_message == message)
 		src.last_message_count++
@@ -79,6 +85,11 @@
 	///////////
 	//CONNECT//
 	///////////
+#if (PRELOAD_RSC == 0)
+var/list/external_rsc_urls
+var/next_external_rsc = 0
+#endif
+
 /client/New(TopicData)
 	TopicData = null							//Prevent calls to client.Topic from connect
 
@@ -87,6 +98,12 @@
 	if(byond_version < MIN_CLIENT_VERSION)		//Out of date client.
 		return null
 
+#if (PRELOAD_RSC == 0)
+	if(external_rsc_urls && external_rsc_urls.len)
+		next_external_rsc = Wrap(next_external_rsc+1, 1, external_rsc_urls.len+1)
+		preload_rsc = external_rsc_urls[next_external_rsc]
+#endif
+
 	clients += src
 	directory[ckey] = src
 
@@ -267,10 +284,4 @@
 		'icons/stamp_icons/large_stamp-cap.png',
 		'icons/stamp_icons/large_stamp-qm.png',
 		'icons/stamp_icons/large_stamp-law.png'
-		)
-
-/client/proc/is_content_unlocked()
-	if(!prefs.unlock_content)
-		src << "Become a BYOND member to access member-perks and features, as well as support the engine that makes this game possible. <a href='http://www.byond.com/membership'>Click Here to find out more</a>."
-		return 0
-	return 1
\ No newline at end of file
+		)
\ No newline at end of file
diff --git a/code/world.dm b/code/world.dm
index c7fa563a996..02cdc3315cb 100644
--- a/code/world.dm
+++ b/code/world.dm
@@ -8,6 +8,15 @@
 #define RECOMMENDED_VERSION 495
 
 /world/New()
+#if (PRELOAD_RSC == 0)
+	external_rsc_urls = file2list("config/external_rsc_urls.txt","\n")
+	var/i=1
+	while(i<=external_rsc_urls.len)
+		if(external_rsc_urls[i])
+			i++
+		else
+			external_rsc_urls.Cut(i,i+1)
+#endif
 	//logs
 	var/date_string = time2text(world.realtime, "YYYY/MM-Month/DD-Day")
 //	if(revdata && istext(revdata.revision) && length(revdata.revision)>7)
diff --git a/config/external_rsc_urls.txt b/config/external_rsc_urls.txt
new file mode 100644
index 00000000000..e69de29bb2d