e.g. forums, instant messaging, Blackboard Collaborate virtual classroom.
Moodle forums
UCL has recently installed the Advanced forum plugin, which shows a nice report of how many times each student has posted, replied and made a substantive post (based on posts flagged as such by a tutor). The Advanced forum also allows anonymous posting as an optional setting that tutors can enable. Apart from these additions it behaves like the standard Moodle forum.
Some staff use Twitter to create a community of students; allows students to ask course-work related questions; get feedback; provide course-work related questions; or make announcements. Here are 50 more ways to use Twitter in and out of the clasroom...
You can embed a Twitter feed in your Moodle course or webpage by using a feed widget from the widgets settings page on twitter.com. Instructions for embedding a widget in to your Moodle course are here...