Shortly after the Google I/O keynote yesterday, Google rolled out a list of app updates, one of which was an update to Google Maps. In the update, Google enabled the ability to save a section of a map for offline access. This is a great feature when you are traveling in an area with spotty coverage.
To save an area, launch Google Maps and tap on the menu key. Select Make Available Offline from the menu and then narrow down the area you want to save. You'll want to make sure you do this in advance and when you're connected to a strong Wi-Fi network. My download of 66 MB took a little over 10 minutes.
Once the download has completed, you'll have full access to that section of the map even when you don't have a data connection.