At work, I use Gmail's chat, since it's encrypted and logs chats without installing or saving anything to the hard drive. At home, I use Pidgin. When I log into GMail at home, I have to log out of chat, or messages will end up in the wrong place. When I log into GMail at work, I have to log back in to chat.

In other words, when I start Firefox at home, I want Gmail's chat disabled automatically. When I start Firefox at work, I want Gmail's chat enabled automatically.

Is there a way to use a Greasemonkey script or similar to force logging in and logging out on specific machines? It would seem simple enough; just follow a URL or simulate clicking a link. Unfortunately, Gmail doesn't use actual links.

While logged out:

<span tabindex="0" role="link" action="si" class="az9OKd">Sign into chat</span>

While logged in, in drop-down menu:

<div tabindex="-1" id=":1mj" role="menuitem" class="oA" value="si"><div class="uQ c6"/>Sign into chat</div>

<div tabindex="-1" id=":8f" role="menuitem" class="oA" value="sia"><div class="uQ c5"/>Sign into AIM®</div>

<div tabindex="-1" id=":8e" role="menuitem" class="oA" value="so"><div class="uQ df"/>Sign out of chat</div>

At bottom of page:

<span id=":im" class="l8 ou" tabindex="0" role="link">turn off chat</span>

<span id=":im" class="l8 ou" tabindex="0" role="link">turn on chat</span>

Anyone know how to "click" these non-links with JavaScript or access their functions? I would imagine that "so" means "sign out", "si" means "sign in", and "sia" means "sign in AIM". Can I somehow call these actions directly?

Is there some other alternative for disabling chat?