reddit is the best social site for discovering new content, breaking news and insight on the internet today. It offers unique "sub"-reddits on individual topics which can range from bizarre (What Would Zombie Steve Jobs Do?) to niche (The Last Airbender). There are so many sub-reddits that there is even a "Random" button at the top of every reddit page to take you to a random sub-reddit which you may not have otherwise discovered. Anyway, here's a list of cool sub-reddits that you should subscribe to in order to save some dough here and there and learn cool new tricks to help you life a more efficient (and economically optimzed) life:
There are a ton of other niche sub-reddits for almost any individual topic you can think. If you can't find something specific you are looking for, try r/AskReddit; reddit is an awesome and friendly community and I am sure someone will have the knowledge and desire to help you in your quest!