Power Point Alternatives

Brainshark
Convert existing PowerPoints into an online video. Fee for some options.

Bunkr
Collects visual content and organize it into slides. Like Evernote for formatting presentations. Built for speedy, easy assembly though not as flexible as Prezi. The HTML5 presentation works on computers, phones and tablets.  Allows for multiple users to work on the same presentation (like Google Docs). Free unless you want to space to store more than two presentations, though you can download them in PDF or PPT.

Clear Slide Alternative to Power Point.

Flair 
Build audio and video with text effects Flash-based presentations without knowing coding for Flash. Not free.

Google Docs Presentations  
Create presentations inside Google Docs. Free with collaborative editing but more limited than PowerPoint.

Keynote
For Mac users, compatible with iPhone and iPad.

Mobile Mouse
Use Your SmartPhone to Give a Presentation. Phone app will control computer. Free version with limited features. MobileMouse Pro, $2.99 for iPad or Android or iOS $1.99. Demonstration video here.

Prezi*
Slide creator. Alternative to Power Point. Use 3-D zoom and turn your slides into a cinematic experience.

Screencast-O-Matic 
Screencasts can be shared on YouTube, embedded in websites, and accessed online.

SlideShare
Popular resentation tool owned by LinkedIn. Use documents, PDFs and video to creat webinars, audio presentations, for online lectures etc. Solid analytics for free. Watch a slide show about SlideShare here.

SlideSnack 
Record your PDFs as an audio-visual slidecast. Basic features are free, more options for purchase.

Vuvox
Multimedia collage tool. Vuvox lets you blend photos, audio, video, and text to create personalized stories. Can’t post directly from Vuvox. Post elsewhere, then embed.  Integrates with social media.