One of the most interesting feature that didnt quite make it into the final release of Firefox 3 is "Private Browsing", a.k.a. porn mode. The only other browser with this feature built-in today is Safari (another reason to try it in case you havent), however, Microsoft may also be building a similar feature into Internet Explorer 8 if two trademark filings are any indications.
Although "private browsing" can be easily associated with viewing particular genres of media content, the Mozilla foundation argues "while viewing pornography may be a popular use case due to the nature of content on the Web, assuming that this is the only reason that users need private browsing trivializes the overall feature. For instance, users may wish to begin a private browsing session to research a medical condition, or plan a surprise vacation or birthday party for a loved one."
If indeed Microsoft is rolling out such a feature in Internet Explorer 8, I can imagine it becoming very popular with surprise birthday planners across the world. Oh those birthday people are in for a treat.