Gmail accounts are web-based e-mail accounts, much like Hotmail or Yahoo; the difference is that you are allowed a whopping 2 gigabytes of space. It also has nifty functions such as conversation tracking, search capabilities within your e-mails and a very good spam filter.
The award of invitations will be discretionary, but the standards aren't strict; basically, only duplicates of material from Debby Wan's site or from this blog (use the search bar at the top of the page to check), or distasteful or irrelevant things will be excluded. You're doing us all a favour, after all. Also, if you have your own site you want to publicise, you will also get a link to it from the blog.
In your entry, include your name or nickname if you want to be acknowledged on the blog, e-mail address (required for the invitation to be sent to you), your site's URL as well as the source of your material, if applicable.
The competition will last until invitations run out. Let the sleuthing begin!