I have two Google Talk accounts – one in the gmai.com domain and the other in ananthapuri.com domain. Sometimes I wanted to have both of the Google Talk accounts running at the same time in my Wondows Operating System. I used to login to the Google Talk web interface as well as the client application for this purpose.
To have multiple ids logged into Google Talk from the same computer, just change the Google Talk shortcut (in Programs or Desktop) to include /nomutex at the end of it and save.
You can also run the program from Start » Run and type “c:\Program Files\Google\Google Talk\googletalk.exe” /nomutex The /nomutex option allows you to open more than one instance of Google Talk and login with different ids.
Check out more cool Google talk tips here. More tips: for bold type *your message* , for italic type _your message_, for line break type shift+enter, use control+tab to switch through open chat windows, etc.. A chat message can be 32767 characters long.