Letters and blogs

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Watt a mistake

"Energy ... in the average human step, roughly eight watts" (A step in the right direction, September 28). Oh dear. Confusing power (energy per second, measured in watts) and energy (measured in joules) is, sadly, all too common. Any chance we could have a version of that interesting article edited by a physicist? The number of joules per step would start to give an indication of what might be possible with this technology.
Tom Ward

See http://tinyurl.com/otvfc - Tech Ed

· 8 Watts per step? 3-6 Watt per step? Dudes! What makes it even worse is that you get it right elswhere: "A typist can generate 19 milliwatts." The watt is a rate unit, similar to speed. "Watts per step" is sheer luddite nonsense.
Glenys Williams-Hesse

· I have never understood why, in the way bicycles create their own lighting, the wheels on trains that just bogie (ie, those that are not drive wheels) cannot be used to provide power for lighting and air conditioning.
Georgeanne Slater

Microsoft's security flaws

Microsoft IS trying to make money by improving security measures (Anti-virus vendors raise threats over Vista in Europe, September 28). Microsoft's OS is full of security flaws, and every security hole has a much higher chance of being exploited because the Microsoft OS is the most widely used OS. Because of these holes a larger number of people are switching to other operating sytems. It is also why Mozilla Firefox is also gaining a larger user base.

It is easy to extrapolate that if Microsoft does not fix these holes they will lose customers - and money. Thus they make A LOT of money by trying to fix the security flaws. And even more when they say they are doing it simply to ensure customer safety.
Sohail Anwar
New York City

· One can easily see how Symantec might consider this "confusing for customers". Before, they had one easy, clear choice: re-up their subscription or have no protection. Now they have choices, and that can be so confusing. I can certainly see why Symantec might dislike a change in Windows Vista that stops them from disabling WSC and, incidentally, ensures customers can find several choices for protection.

Follow the clickprint

· This is bogus (Is it possible to be identified by your "clickprint"?, September 28). Even if they can often distinguish between me and another anonymous person, it wont be 100% correct. I don't want to be considered for fraud under my own cards.

No rest for the Wiki-ed

· On the mailing list WikiEN-L is a law of Wikipedia that should become known as the Finkelstein Paradox (I'm on Wikipedia, get me out of here, September 28) - a subject who argues he doesn't belong in Wikipedia is more likely to remain in Wikipedia.

Brit credit's no good

Interesting article, but Kate Bevan's experiences with French petrol pumps were caused by a different sort of problem (Technobile, September 28). As far as I know, these pumps currently only take French credit cards, not UK ones. I've also found that some restaurants etc still require a signature, not a pin, for UK cards.
Colin Blakemore

A clone-free zone?

About the time of your piece on inkjet cartridges (Technobile, September 14) my printer gave up the ghost, and reassured that I would still be able to buy cheap cloned cartridges, I replaced my Epson inkjet with another Epson. But when I went to Cartridgemonkey, I found a grovelling page of praise for genuine Epson cartridges but no sign of cheap clones any more. Did Epson read your article and fly into a rage?
Penny Munday