The Starcraft Command
This is a good technique in a 2on2 game or even a 1on1.
You begin by building 6 SCV's and putting them on your minerals. Then you make a 7th SCV and with him you build a barrack. Then you build another SCV and build a supply depot with him. After you are done with these buildings put 1 of the SCV's on minerals and with the other build another barrack.Continue to make SCV's and put them all on minerals. Then you build a third barrack after the second is done. Then you should build 1 or 2 marines and scout with them. When the third barracks is one build a fourth barracks.
After this you must build another supply deopt. And then when you have 4 barracks start to crank out marines like hell. As well as continuing to build SCV's. You should also build a refinery and an academy (if you want).
During this time you should be continuing with building supply depots because you will run out of supplies quickly.
When the Academy is finished you should upgrade stimpacks. I usually don't build an Academy or a Refinary. I only do so, if I can tell that the game is going to last longer than 15 minutes. But when you crank out marines like this and have teammates to back you up you ususally don't have a game that lasts longer than 15 minutes.
This is also a great way to assist your friends in their rush attempts. Otherwise its usually zerg players that rush but now you can help them out.