After the Deadline is a free open source software using artificial intelligence to check spelling, style and grammar while you write, while many applications include spell checking software, very few check your style and grammar as well. After the Deadline pinpoints and underlines errors with different colours (red spelling, blue grammar, green style) giving you a suggestion of what the correct linguistic style is, if you do not want to change a specific word, like a place name, and it is highlighted, simply choose to always ignore it, creating your own custom dictionary in the proces.
After the Deadline free spell checker
This tool can be used with your blog (WordPress plugin), integrated with your browser installing a Firefox orChrome plugin (very useful to fill in online forms), OpenOffice.org text editor, Windows Live Writer and a few others, my favourite feature is the integration with IntenseDebate, a blog comment management plugin, After the Deadline will warn people commenting on your blog of grammar and spelling mistakes.
The only inadequacy I found in this spell checking software is that it does not differentiate in between American, Canadian and British English, all words variations are mixed up in the dictionary but it appears that After the Deadline plans to solve this at some point in future, another downside is that your application needs to be supported for it to work, you can not use it with Microsoft Word for example, overall this is a good proofreading tool for the home user but not for business use.
Visit After the Deadline homepage