As a teacher, it is important to make use of our resources and in a TEFL classroom there are different 'technological' resources that teachers can consider using in the classroom:
1) Twitter - this is a good tool to stay in touch with your students and this tool also helps students to write in shorter and more concise sentences.
2) Posterous - having posterous is a good way to keep your students informed on what is going on and is a good place to post announcements and important information for the class. Students can also comment and read other comments from their classmates.
3) YouTube - There are a variety of clips that teachers can find on YouTube to help students with learning English. A classic example that is used in most classes is the clip from My Fair Lady. YouTube is also a good way to show snippets from American movies or dramas.
4) Song/Podcasts - Using music is a great way for students to learn English. Students can choose songs from singers that they like and teachers can teach English through the lyrics. Podcasts are also a good tool for students to hear American radio shows.
All of the resources mentioned above, are free as long as you have access to the internet. I think all these resources are good ways to help students become more engaged in the class.