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An anonymous reader writes "This article at LinuxDevices.com describes an interesting project at the University of Vermont in which researchers use real-time Linux to build a laser trap that manipulates individual molecules by means of a computer-controlled laser beam. The project makes use of RTLinux, a real-time enhanced version of Linux that allows the system to process interrupts every 50 microsecond, sample new data, and timeshare the laser beam position. 'If the computer failed to respond, for even a millisecond, then we would drop the balls,' explained one of the researchers. Gives a whole new meaning to BSOD, eh?"

An Anonymous Coward writes: "This story by LinuxDevices.com founder Rick Lehrbaum provides in-depth coverage of today's important joint announcment by Red Hat and FSMLabs of Red Hat's adoption of RTLinux as its real-time Linux technology of choice. The article is based primarily on interviews with Michael Tiemann and Victor Yodaiken, has a comment from Alan Cox, and includes numerous links to further details and background information. Guess it's time for another round in the never-ending debate over real-time Linux architectures!"

BSD Today reports that embedded RTLinux company, FSM Labs has decided to move into NetBSD as a general purpose OS layer to RTLinux APIs. This is following Wind River's acquisition of the software assets of BSDi. Makes one wonder whether the competition in the BSD arena is about to begin.

Here it is again. Back atcha with stuff on ... the actual sex of Tjisana M. Lewis and other foul-ups; Richard Stallman's back-in-proportion response to the out-of-same brouhaha over licensing of KDE; and a reaction to the announcment last week of a fully-preemptive kernel. Not to mention a few followups to the piece Rob posted last week about Amazon's interesting pricing policies.

Shouldn't this be one of those fields marked "required" on e-mail? Tjisana M. Lewis wrote: "Just one minor issue though in case we meet again - I (Product Manager with titles ad nauseaum) am male." (I had written -- with the famous line about 'what happens when you assume' nowhere in mind -- that "she sent the following response ..." regarding the new HP printserver which as of now does not support printing from Linux clients.) With apologies and thanks for the correction, I await the beating with wet noodles. declan points out another goof for which I must shoulder the blame: the judge in question in the DeCSS case is Lewis Kaplan, not Chaplain, as rendered in this story of last week.

Calling Tim Theisen, calling Tim Theisen to the white courtesy telephone ... Richard M. Stallman can't win. At least, that's the impression one gets sometimes from hearing the reactions he draws for saying nearly anything. Critical or glowing, the man says what's on his mind, and there's plenty on it. Including, of late, plenty about GNOME and KDE. As usual, the whole story is both more complex and more satisfying when you know more about it. Several readers pointed at Stallman's response at LinuxToday to the criticism he recieved (both official and unofficial) after he said "Making Qt available under the GPL makes it legal to take an existing GPL-covered program and adapt it to work with Qt." As a happy user of both KDE and GNOME, I must say RMS sounds pretty reasonable to me.

And a special deal for our guests from AOL -- Two bridges! Amazon says: don't worry! It's just an accident! jeko writes "Amazon.com just sent me an email claiming that their different prices for different customers are merely a mistake."

He cites email from a customer rep at Amazon:

"Finally, at any given time, despite our best efforts, a small number of the more than 4.7 million items on our site may be mispriced.

Kristine Jorgensen, Amazon.com"

"So, there you go. This latest PR row is all just a 'mispricing.' I wish my customers would let me get away with that."

Meanwhile, Amazon is apparently not the only company to play cookie-based pricing games ... An unnamed correspondent writes: "[...] Similar to your story on Amazon.com regarding price differences, I think I've found a similar ploy on flyfrontier.com. I've been checking flights from Washington, DC to Denver, CO. When I first checked prices, the flight came back at $400. Several minutes later, the same flight was priced at over $500. When I switched computers, the same thing happened again: The price on the same flight was $400 in the first instance, and over $500 on the second. Then, I switched browsers ... it happened again. When I cleared my history and disabled cookies, I was able to recreate the price difference again. Try it and see for yourself. So, what's up with this? What is the advantage of switching prices around? Has this practice become widespread on the web?"

You have exactly 15ms to complete your response ... Go. Rick Lehrbaum writes "Victor Yodaiken, creator of RTLinux, has provided a brief statement about MontaVista Software's recent announcement of a hard real-time Linux (MontaVista, it should be noted, supports both RTLinux and the new kernel preemption technology.) In his response, Yodaiken draws significant distinctions between the architectural approaches taken by each (RTLinux; kernel preemptability), provides a technical perspective on the usefulness of each, and mentions some issues that need to be considered in proceeding along a kernel preemption path (which he does *not* summarily dismiss). Yodaiken claims that under RTLinux, "real-time software can communicate with Linux through fifos, shared memory, or signals but still gets hardware speed interrupt latencies, RTLinux worst case interrupt latencies are 15 microseconds on a generic x86 and better on PowerPC and Alphas." Additional detailed background on RTLinux appears in this interesting interview with Yodaiken (including info about "the infamous RTLinux patent")."