This may be old news, but it's also the kind of "old news" that's actually becoming more and more relevant these days. ;)
- The SQL Server 2008 Books Online Scoped Search macro.
Those of you who've found the 'old' one useful, must have been anticipating the 'new' one.
Personally, sometimes I really don't know what I'd do without them – providing a friend in need with a 'live' link to a specific Books Online article has never been easier. :)