I use dasBlog as my blog engine and I've recently upgraded it to a newer version (not an official release). One enhancement that was added by Scott Hanselman is support for MIT's Simile Project Timeline control. Timeline is "a DHTML AJAX timeline widget for visualizing temporal information" that supports scrolling (via the mouse like Google maps). You can scroll the control by day or month as well as highlight and filter the data. DasBlog is setup to create an XML file used to populate the timeline dynamically based on blog post data. The control is available freely for you to use in your own applications and doesn't require much to incorporate it. If you haven't seen it before I think it's well worth a look.
NOTE: I've tested it with my blog layout using Firefox 2.0.0.3 which works great. It causes some funky sizing issues in IE6 & 7 but it's just cosmetic so not a big problem.
[UPDATE Nov. 12, 2009] I've since changed blog engines (dasBlog to BlogEngine.NET) this feature is no longer available. For an example, click here
Google Simile Timeline