For people who prefer Internet Explorer as their browser and do not currently have a spell checker utility plugin, check out ieSpell. This free plugin is specific to IE and offers many features you might not find in spell checkers included with other tool bars, such as (copied from ieSpell’s website):

• Completely standalone spell checker for your web browser. Does not require Microsoft Office or any other third party components.
• Supports a wide range of web applications including simple text forms, rich text editors, forums, blogs, webmail (including Outlook Web Access and Lotus iNotes) and more!
• Integrates with Microsoft Office’s proofing tools. Have ieSpell share the same copy of the custom dictionary so that when you add/remove your personal words in ieSpell, the same is reflected in Microsoft Office and vice versa!
• ieSpell suggested a word that you are not familiar with? Look up its meaning in an online dictionary!
• Powerful API for web application developers.

Again, if you do not already have a general spell checker for IE, this is definitely worth a look.