While surfing about the net I ran across a nifty tag cloud implemented as a flash movie, WP-Cumulus. Unfortunately, it was a wordpress plugin[?]. Fortunately the creator, Roy Tanck, was kind enough to not only open source WP-Cumulus, but to provide tips on how to incorporate it into other web sites!
So I hacked it into my local blog (sorry for the down time ) and got it working with hard-coded parameters, then migrated it into the freetag plugin that Serendipity has. Garvin (the creator of S9Y) made a few improvements, and it is now bundled into the application, and available via Sparticus, the S9Y online plugin manager!)