In Google Maps the "Link to this page" option produces very long url addresses. This isn't very helpful if you wish to link to a location in Twitter. If you need a short url for Twitter or FriendFeed then you can instead use a service such as Plazz.me which produces short web addresses for Google Maps' locations.
Plazz.me is very simple to use. Enter your address into a search box. If the given address is not exactly correct drag the marker to the correct location. Then press the 'Create a Short URL' button. And that's it, Plazz.me will return a short url that you can then send to your friends to show them your location.
By way of comparison here is the Plazz.me url for the White House and beneath it is the url for the same location as produced by Google Maps.
Barry Hunter (one of the Google Maps Discussion Group God's) alerted me (via the comments) to the amazing service provided by mapof.it.
mapof.it provides a really simple way to get a map or a route without first visiting Google Maps. To do this you simply type the address including your search parameters after the first slash...
mapof.it/... and you will be taken to a map of your search. Enter two locations with a slash between them to see a route between the locations.
Here are some examples:
Although Google Maps is the default map service there is even a way to get other map services. But you'll have to discover that for yourself.
Other Google Maps URL Shorteners
UseAMap.com - Zoom to a location and choose your url.
LookLeap - Add this bookmarklet to your browser. Click the bookmarklet when you want to create a small url.