In a nasty blow to WiMax technology in general, Sprint today announced that it had terminated its letter of intent to work with Clearwire on a nationwide WiMax network.

It's also, of course, a nasty blow to Clearwire. "Shares of Clearwire fell $4.54, or 25 percent, to close at $13.49 after sliding as low as $13.03, an all-time low," notes the AP's Peter Svensson. "The Kirkland, Wash., company founded by wireless pioneer Craig McCaw went public in March at $25 a share."

"Any slowdown in the rollout of WiMax by either Clearwire or Sprint would negatively impact companies that are backing the technology, including chip maker Intel Corp., and equipment makers Motorola Inc. and Samsung Electronics Co.," writes the Wall Street Journal's Amol Sharma.

Still, it's not the end of WiMax for Sprint - and as Computerworld's Matt Hamblen points out, it's not the end of the road for Clearwire either. "Potential new partners with Clearwire could be satellite operators or even Google Inc., which expressed interest in purchasing 700-MHz spectrum at a federal auction in January that could be used with WiMax," he writes.

More here from Wired ... more here from InformationWeek ... more here from the Seattle Times ... and the press release is here.