Wikis
The short URL for this page is
http://bit.ly/MAELT_wikis.
Nik Peachey recommends Wetpaint in his ICT blog. He includes several instructional videos and describes the pros and cons of Wetpaint. In a later blog entry, Nik demonstrates how wikis can be used with EFL students, and later again in teacher training.
If you opt for a free account with Wetpaint, you can request an ad free educational registration. This is also the case with PB Wiki and Wikispaces.
Moodle has a wiki module.