Google's Data Highlighter makes easy for web masters to do markup for pages having events and helps show the event data better and improve your looks in search results page.
What's really cool about this tool is that you can highlight a single page by submitting the link or for an entire site having pages with events data which are similar in structure for event info.
This tool may not be useful for most bloggers and info sharing site, but if you have a site which involves with dates, events, selling, product release etc. then it'll be good for you.
Once done you can simply publish your page and relax.