SlideShare Office 2007 Plugin

From https://www.techcrunch.com/2008/12/15/slideshare-sends-powerpoint-to-the-cloud-with-new-plugin/: 

SlideShare, a startup that we’ve likened to a YouTube equivalent for PowerPoint presentations, has released a new plugin for Microsoft Office 2007 that allows users to edit and publish presentations directly to their SlideShare accounts. You can download the free plugin here.

Beyond publishing new PowerPoint documents to the web, the SlideShare plugin can import SlideShare files from the cloud (both your own and those that are shared by others), which can then be modified on your native PowerPoint client. The plugin features an integrated search so you can browse through files from your SlideShare contacts and groups, as well as support for Twitter and FriendFeed so you can broadcast a new presentation without leaving Office.

Thanks FrankArr for the tip!