I've written widely about using Web 2.0 and social media tools to introduce and teach mini lessons. Here is an example of using the podcasting application Voki to launch a strategic reading activity.
After the brief podcast, I place simple, short step-by-step instructions for GIST on the Interactive White Board, and the students are soon working the strategy in small groups.
There is no more than three minutes of direct instruction, not including the Voki. So, as I always tell the students, it's less from me and more from them.
Of course, they love it this way, and they learn a lot more.