Create a badge which normally look like your company logo. This badge will have your webpage link coded embedded into it. You can use it on your social media sites as your profile picture so when people click on it they are brought to your web page. Look at http://www.freshbadge.com for examples.
If you are having an event it is a good idea to create a hashtag, this will help you follow who are tweeting about your event. Before you create a hashtag go to http://www.hashtags.org to ensure you create a distinct hashtag relevant to your event. A hashtag looks something like this #technology, #eventdublin2011.
Like Facebook, Twitter has such a large community hastags make it easier for people to find you message. I was surprised to hear that twitter didn’t invent hastags – have a look here http://tinyurl.com/6a2gm8s