twitter is a great social media tool. it is sometimes referred to as a "microblogging" tool as well. instead of writing long "blog" entries, you are limited to 140 characters per "tweet". there are games and groups that you can join. for example, Artwiculate is a word of the day game which challenges players to come up with clever tweets using the designated word of the day and if people like your tweets they Retweet it (which means they re-post your post).