There are many websites where someone can sign up with a login and be paid to answer questions. Some of these sites include questions that users text in to the site, and some are Internet-based question-and-answer sites. Not all question-and-answer sites provide monetary compensation for question answering, however.
There are several sites that are question and answer sites that are text- or MMS-based. These include ChaCha, Weegy and KGB Answers. The pay rates and rules differ per company, and it is best to go to each website and understand the terms of service before beginning. There are other sites that answer questions via the web, such as FixYa, Directly and Answers 123. JustAnswer is also a popular website that offers compensation for questions. Again, each site's terms of service and pay rate vary.
There are also many sites that do not provide monetary compensation for answering questions. However, these are good sites on which to practice one's writing and gain some experience. Sites like these include Yahoo! Answers, WikiAnswers and Answerbag. On these sites, other readers rate the answers to questions based on their quality and ability to answer the question. There are also sites that provide compensation for articles written, such as Demand Media. This may be of interest to more experienced writers, or those that have an area of expertise.