ヅラッシュ！ by NI-Lab.

How can I easily change my location on the map?
Simply send a Twitter update that includes 'L:' followed by your location. Examples: 'Going to the office. L:3000 6th Ave, New York', 'L:Rouen, France', 'L:Disneyland', 'L:Las Vegas, NV', 'L:EWR', 'L:90210', 'L:30.010,-90.007'. There is no need to specify lat:, long: when giving coordinates.
Can I update between home, work, the bar, school, etc?
Yep! Now you can define location macros which you can use to quickly update your position.

　　* L:home=517 Spruce Ln, Lenexa, KS 60502
　　* L:work=300 Alameda Parkway, San Jose, CA 92012
　　* L:sarahs=Rue Ducasse 75, Paris, France
　　* L:tim's=Auguststrasse 5, Berlin, Germany
　　* L:parents=Burnside Cr, Melbourne
　　* L:owl bar=1000 Charles St, Baltimore, MD 20507
　　* L:school=3700 University Blvd, Berkeley, CA 95010

Once these are setup you can move from place simply by including 'L:home' or 'L:work' in your updates! Now it's easier than ever to update your position! Here are some more examples of valid and invalid locations.

twittermap faq

Valid Location Setting Examples
The following strings are examples of how you can correctly set your location and use personal location definitions on Twittervision and Twittermap using Twitter updates. Personal locations can be defined using the format L:place=address, where place can be any easy-to-remember word.

going to l:home, then to bed
l:arvada, co for now
l:work, for now
l: bar=500 nyals st, chicago
l:work=123 main st, annapolis, md
l: school=320 smith st, columbus, ga: ok?
will it find me in l:nyc?
l:80201
l:disneyland
l:200 Broad St, Philadelphia, PA
going to the l:office
back l:home for some rest, finally
just arriving at l:work, hoping it won't be a crazy day
never to early to go to the l:bar! meet you there
sigh -- l:124 main st, 80303: but wishing I was at home
l:304 Samuels Rd, Newton, WV: through thursday
no time right now l: fiske st, toronto: party tonight anyone?
now going to L:school, wich stinks
You do not have to define personal locations (say for a short trip), but can instead update your location to any geocodable location using the format L:address. You can also separate location-setting from the rest of your message with an additional comment.

For you tech types, the valid supported syntaxes are:

L:place=address[:] store a personal location
L:place[:] set a stored personal location as current location
L:address[:] set an arbitrary location as current location
Note:

　　* place may be one or more words; one word is preferred.
　　* address may be any geocodable location. Use Twittermap search to search on a location before specifying it in an L: tag if you are not sure it is valid.
　　* L: is case insensitive, so you can use l: too

twittermap faq

・さて、緯度経度が分かったところで、いよいよTwittermapに登録だ。といってもTwitterでいつものように発言するだけ。 TwittermapはみんなのTwitterの中から、L:と書かれた情報に反応するように出来てるらしい。homeという名前で家の場所を登録するには朕の場合なら、
L:home=35.685374,139.753097
と入れれば良い訳だ。数字部分はもちろんさっき調べた緯度経度に書き直して登録しよう。ちなみに、homeというところは好きな名前で登録できるよ。workとかnezumiilandとかなんでもOK。よく行く場所を登録しよう。
さあ登録。と先走った皆さん、登録できなかったでしょ？僕はダメだった。
ここでいろいろ試行錯誤した結果、魔法の呪文を発見!!
Updating my location. L:home=35.685374,139.753097
これで登録できた。
魔法の呪文って言うのはまたしても多分嘘なんだけど、なんか英文と一緒に書けば反応するみたいだね。登録時は日本語は書いちゃダメみたい。僕は、 twittermapでうまくやってる人を探して、その人の登録の発言をコピペして登録してみたら、うまくいったので、毎回この人の発言をコピペしてるというわけです。ありがとう○○○○○○。
滅多に行かない場所で登録するまでもない場所なら名前を書かずに
L:35.685374,139.753097
みたいな感じでもOKみたいだ。こっちももちろん呪文付きでね。

TwitterとかTwittermapとか | しじま