The first is as a way into mobile for non-mobile players. Worthington says he's seeing plenty of interest from ISPs, cable TV guys and satellite operators. Mobile will never be their core business, but a wireless data/voice offering broadens their product set.
The next - and this could be its biggest app - is in M2M, or man-to-machine. The idea of embedding chips in thousands and thousands of cameras, MP3 players, home networks, vending machines, to name but a few, certainly excites the WiMAX community. These would be deployable in multiple spectrum bands and would build on the growing installed base of embedded Wi-Fi devices.
The final one is the bet by Nortel, Intel and others to make WiMAX a foundation of 4G. That one's with the standards bodies right now and doubtless will remain there for years to come.
There may well be a killer app lurking inside WiMAX. We just don't know which one.
Robert Clark is a Hong Kong-based technology journalist. His blog Electric Speech is at
www.electricspeech.typepad.com