I use flow charts all the time when designing websites, brainstorming articles and writing posts and more.  I use a desktop application, well I did until I came across Bubbl.us

Bubbl.us, a flash based (and therefore web based) application for creating good looking flow charts.  The great thing about Bubbe.us is its simplicity.  Like many web 2.0 apps, it requires no documentation and I created a chart in just seconds.

It comes with all the features you would expect - saving, printing and zooming and best of all its free.  The only thing I would like to see added are some sharing features.
This is another site that has taken, what could have been a complex solution and made it simple.  Top marks for Bubbl.us.

Visit www.bubbl.us