Doing my fluffy-Friday reading I found this post on Scot Hanselman's blog about a tool named RockScroll that turns your VS2005/2008 scroll bar into a thumbnail view of the open document (when working with .cs files anyway). It also has a nifty feature that if you double click a word in the source code, say a variable name, it will highlight all occurrences of that word in a lovely lilac color (and red in the thumbnail scroll bar - which is the useful bit, IMO).
Anyway, I'm digging this new tool and hope you might also find it useful.
