Here's an utterly excellent post from a new favorite, The Bamboo Project blog by Michele Martin. Michele shows how small nonprofits can use the web -- for an investment of $60 or less -- to communicate with clients, donors, advocates, volunteers, and other supporters.
Just as good is this one, from the same blog, on how nonprofits can benefit from Facebook.
nonprofits, nota bene: I use Typepad for studio 501c, and recommend it for the same reasons that Seth Godin (who inspired Michele's post) does. For a more comprehensive web site, I recommend ExpressionEngine.
You can also publish a blog for short-term communications objectives. Here's how Naisy Dolar, a Chicago aldermanic candidate, used a blog to chronicle election-day happenings in a recent run-off in Chicago's 50th ward. Published with Google's free Blogger service, the blog was an efficient way to communicate with supporters and the press throughout the day.
Nonprofits could do the same for special projects and events, e.g., a marathon, a field trip, a clean-up day, an art project, or construction of a building.