One way or the other, most of the technology inventions that have been the stuff of my day to day work for the last 5 years have had their source in Dave Winer. We used Dave's scripting language for the Mac, Frontier, to build e-commerce systems at Okeedokee. Dave pioneered blogging, RSS, and podcasting.
In the fall of 2003, Dave was an accidental guest at Zap Your PRAM when, after speaking at another conference happening on Prince Edward Island the same weekend, he came along to Zap and jumped right in.
You can see Dave blog and podcast at Scripting.com.