For a long time, users of Windows browsers have been able to view and click on URLs that start with aim:, allowing automated instant messaging operations from web pages. It looks like Apple has finally integrated iChat AV and Safari 1.0 to support this sort of URL as well.
Clicking on a link like this one will launch iChat AV. You can also automatically add buddies and send messages using the same aim: URL syntax. More info can be found on AOL's AIM Remote pages.
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