4. It Modernizes the Telephone

Why call when you can video chat? Web 2.0 brings into the mainstream new ways for people to reach one another - even though many of the technologies that allow this communication have been around since Web 1.0. Webmail has replaced the old-fashioned email client (that is, software), making your messages accessible from anywhere. When you're at your Mac, iChat and other instant messaging (IM) apps have replaced email as the go-to method for on-the-spot communiqués.

Web 2.0 brings these different modes of communication together: You can send text messages to your mom's cell phone from the Internet, for example. With iSight cameras built into iMacs, MacBooks, and MacBook Pros, video chat is an everyday reality for those with bountiful bandwidth - otherwise audio chat is the next best thing. In between is one of Web 2.0's true killer apps, voice over IP (VoIP). It's the useful evolution of Internet telephony, which has been around longer than the Web itself. VoIP uses Internet protocol (IP) technology to send voice data over Net connections, offering you a set monthly fee rather than per-minute call charges, and the ability to access your VoIP account from anywhere in the world to make local calls.

But VoIP has a few drawbacks, mainly its dependence on the Internet. You can't spell VoIP without IP, and you can't use it without Internet access. That means that you can't use VoIP during a power outage - although many cordless phones don't work when the power's down either. The equalizer: Public Wi-Fi networks and portable VoIP phones are on the horizon and will greatly increase VoIP's functional reach.

5. It Works for Work, Too

It's 2007. Shouldn't we all be telecommuting by now? Actual businesses are using Web 2.0 technology to streamline everything, from information dissemination, to group collaboration on documents and projects, to group scheduling - all, as business types like to say, "on the same page." Most businesses use the company intranet for such things, using commercial or custom software to create a virtual all-staff meeting place/information clearinghouse that only authorized users can access, and usually only when they're within the company's physical walls - or outside via virtual private network (VPN) connections. Progressive companies are implementing the social aspects of Web 2.0 as well, doing things like installing company wikis where worker bees, managers, and bosses can share ideas.

Web 2.0 also makes telecommuting and collaborating with far-off colleagues more efficient and secure. Trick sites like ThinkFree (www.thinkfree.com) and Google Docs & Spreadsheets (docs.google.com) offer collaborative work spaces where colleagues across the globe can work on documents together in real time, regardless whether they're on a Mac or ... something else.

6. Your Photos Can Do More Than Just Sit There

Web 2.0 apps let you edit, animate, stitch together, and of course share photos online for free. As an antidote to all of that workaday productivity, Web 2.0 brings mature versions of early-Web treats like GifWorks, which, since the late '90s, has let you create cool little animated GIF images for your home page (it's still going strong at www.gifworks.com). Web 2.0 ups the ante with sites like Picnik (www.picnik.com), which provides useful photo-editing tools (autofix, rotate, crop, resize, exposure, colors, sharpen, red-eye removal, and more) in a Flash interface. Meanwhile, CleVR (www.clevr.com) helps you stitch contiguous shots of a scene into a fully navigable VR movie or a flat panoramic image. Both sites also provide easy sharing options, such as precoded snippets for adding the output to MySpace or a personal site.

Sites like Picnik let you edit photos before sharing them.

7. It Brings TV to Your Mac

Go beyond YouTube clips of half-drunk college kids. The future of online video is feature films in streaming HD. But while the lawyers work that out, you can watch television programming online. All three major networks offer their most popular shows for online viewing, and the iTunes Store has plenty more. More interestingly, if you still watch TV shows broadcast the old way, you may have noticed that most of the big shows run a teaser at the end inviting viewers online to see the full episode again, and/or watch deleted scenes and cast interviews, and read cast blogs. You can even get TV content piped onto your AOL, Microsoft, or Yahoo home page.

Meanwhile, user-driven video sites are still going strong. Viddler (www.viddler.com) takes tagging a step further, letting you tag specific moments in a video, rather than just the video itself. And promoting the "everyone's a reporter" mentality of Web 2.0, LiveLeak (www.liveleak.com) prompts users to upload "newsworthy" videos that they captured by being in the right place at the right time.

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