Sharing Slideshows Easily

I like that there are several Web 2.0 tools to share slideshows easily. It is great to not have to use email attachments anymore to share slideshows or rely on that everyone has PowerPoint software because the slideshows can be viewed on internet browsers. You can also have access to the slideshows anywhere you can reach the internet. I particularly liked SlideRocket because it had a great deal of support and offered a collaborative function, but it costs money after the free trial. Unless I overlooked that function on the other tools, each of them seemed to just be means to share slideshows, find slideshows by interest, discuss slideshows, get feedback, and have access to them on the web.