Forget PowerPoint: 13 Online Presentation Apps

Mashable has a great article: Forget PowerPoint: 13 Online Presentation Apps. The products that they suggest you take a look at are:
AjaxPresents
BrinkPad
Empressr
Google Documents
Preezo
Presentation Engine
PreZentit
SlideRocket
Spresent
ThinkFree
Thumbstacks
Vcasmo
Zoho Show

However, there's also SimonShows and a host of others mentioned on my 'I want to' weblog under Collaboration: presentations.