Log in to your XBOX Live dash and you'll see an advertisement mentioning $2 for 2 months of Live Gold membership. XBOX is often having deep discounts on their Live Gold membership and you should take advantage them. I've gotten about 2 years worth for less than $20 with these promotions. You can play online, watch netflix, listen to music, video chat via your kinect, etc. :) Just click on the advertisement via your dash, enter a credit.debit card (or use the one you already have saved on there) and there you go. It auto-renews at its regular prices after the 2 months so make sure you cancel beforehand if you want.
Enjoy it guys!