Just a short alert regarding the Skype worm going around: If you use Windows and if a friend sends you a Skype instant message that contains a link to a JPG picture file, don't click on that link.
However tempting it may be, whatever promises your friend might make regarding the awesomeness of the picture (it'll be that kind of picture), you're better off clicking elsewhere for your jollies -- for you may find that instead of going to a picture, the link actually opens up a prompt to run an application. And if you're so foolish or hot-under-the-collar as to actually click Yes to that prompt, well, then you're screwed, as it were.
If it gets in, the worm uses the Skype API to send itself to all your Skype contacts. It also searches your machine for passwords and other sensitive information to send back to the nefarious fellows who created it.
Skype says it's working with anti-virus vendors to create updates to stop the worm, and it's trying to get ISPs to shut down the sites spreading the virus. If you think you might be infected -- why'd you click on the link, man? -- click here for a cure.