I run a small Web development company and use Adobe Systems' Flash. I am considering adopting Adobe Flex, a new cross-platform Web application framework, but recently read about the Linux-supporting Microsoft Silverlight. Is this a significant development? Name and address supplied DQ: All developers would welcome Microsoft's support when it comes to other platforms. Silverlight - cross-platform, cross-browser, plug-in software used by developers to build rich media applications on the Web - has received a lot of interest. But it's still early days. The final version of Silverlight 1.0 was made available for download only this month and it faces stiff competition from Adobe. Your question also has larger implications. Small companies must spend a considerable amount of money on development tools. If a firm picks the 'wrong' one - a software platform that does not become pervasive or popular - it's in trouble. While it's good Microsoft is supporting Linux, Mac OS X and its own operating system, even a company of its size will find it difficult to promote a new platform. Don't throw anything away yet. Regarding William Lo's question (August 12), I recommend a spyware scan of his personal computer in addition to defragging the hard disk. Some spyware could be hogging his PC's resources. I have used IObit's Advanced WindowsCare Personal Edition for about nine months. Mukesh Balani, Hong Kong DQ: You are correct to point out that spyware could be the problem. Spyware key-loggers, which capture every keystroke, can easily steal passwords. Also, Apple spoke to me about my comment on not needing to defrag an Apple computer's hard disk. The engineer said that for a system disk - one on which the computer system boots - what I wrote was true. But it may not apply if other disks are attached to your Apple computer. While the Apple system disk's design enables it to 'take care of itself', that is not always true for other disks. A Mac-user friend says he runs a low-level initialisation of all new discs on his system.