A new service called SlideShare is becoming quite popular for sharing PowerPoint presentations via the web. The service lets you upload your presentations to the web, where they can be shared publicly with the world or privately with those you choose.
Once uploaded to the SlideShare service, you can then embed the presentations right onto your web site - something which makes it easy to share information with your customers if you're running a business or provides an easy way to share slides with your friends if you have a personal web site or blog.
In addition to PowerPoint files, you can also use SlideShare to upload PDFs to the web.
The files can be as large as 50 MB in size, which is a lot more than competitors offer, like 10 MB at Zoho Show, for example. Plus, it's much easier to share your presentations than try to compress them into an email.
Best of all, SlideShare is free!