Do you need PowerPoint (or Keynote) to create presentations? Perhaps not. There are several good Web-based solutions, including the newest (to us), Spresent. This online presentation service lets you quickly create decent presentations that you can deliver from any computer with a Web browser.
Spresent competes with other online apps such as Thumbstacks and Zoho Show [see comparison]. What sets Spresent apart is its slick Flash-based user interface and tight integration with other Web services. Need a picture of a mountain or an octopus to go along with your bullet points? Spresent has built-in Flickr browsing, which pulls up previews and URLs without leaving the presentation-building experience. You can also embed YouTube videos. When you're done with a presentation, you can share it three ways: save and send the file to another Spresent user, e-mail it as a self-playing file, or use the Embed link to put it on Web sites.
Is Spresent a serious competitor to PowerPoint? With its multiple export options and standardized Web-format compatibility, it does make it harder to justify purchasing actual software. Spresent does not have all the features of PowerPoint, though, and its user interface is different enough that it will slow down PowerPoint jockeys. And you can't easily use it offline, so doing last-minute editing of your preso on the airplane is out of the question. But for infrequent presenters, especially people who don't want to pay for software they'll rarely use, Spresent is good solution.