I just noticed that Google add automatic Map Links when something that looks like an address appears within a message in Gmail.

This kind of on-the-fly detection of metadata to create searches could be used for auto-dialing phone numbers or adding appointments to a calendar - but I guess we'll have to wait for a Google Calendar product for that.

"Gmail makes it easy for you to keep track of your packages, and map out directions to your destinations; when you open a message that lists an address or package tracking number, Gmail shows you handy links to maps and directions, or your package's delivery status."