Searching through del.icio.us, I found some useful sites which provide podcasts.
- Better at English: here you I can find a wide range of podcasts to improve my skills in English. The site provides also online listenings and transcriptions, and all the material is divided into three levels (intermediate, upper intermedaite and advanced) and into different grammatical topics (phrasal verbs, business English, idioms and slangs, vocabulary, ect.).
- Libri Vox: a funny way to learn English could be listening to these free audio books (which means that they have no copyrights). You can choose among a huge number of title and genres and, if you just want to make yourself an idea, you can download only a chapter.
- EnglishPod | Learn Business English with Daily MP3 Podcasts:I think the title is clear enough. This website teaches you what business English is and how it has to be used in the different situations: relationships, presentation, inviting, being diplomatic and so on. In each "lesson" you are followed by Scott and Jessica, whose voices I found very friendly and relaxing. Very interesting!

