Some tips for starting an 'activity-centric' wiki:

1. Pick a project or activity you are involved with or leading - ideally, one that is current and has several emails going back and forth amongst the team members (and others, if appropriate).
2. Collect all the relevant emails you can get your hands on including the document attachments.
3. Based on the emails, the project objectives, etc, draft an outline of the project as if you had to give a presentation to someone as to the project purpose, history, status, next steps, current activities, issues, ....
4. That outline is your wiki HomePage (or FrontPage or MainPage or whatever depending on the wiki engine you're using). Copy it into your workspace Page. (Optionally, take a key phrase from each line of the outline and make it a page link.)
5. Now - copy the content of each email somewhere into that outline OR Pages you are linking to from the HomePage.
6. Don't start editing yet. You want it to look familiar to your audience. If anything, you may want to preface some of the email content with the person's name who sent it ('Jane wants to know >', Carl commented >', 'Here's my suggestion >', .....)
7. Before you invite the audience in, take a step back and ask yourself "If I was looking at this for the first time and someone was expecting me to understand it or contribute something, would I get it?" Probably not, so start tweaking it a little and add some introductory comments on the HomePage

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