To install Google Pinyin silently, you can use the following parameter, no admin rights required:

Parallel as-you-browse pronunciation hints for Chinese, covering Mandarin (Pinyin), Cantonese (Yale, Sidney Lau or Jyutping) or Teochew, with word grouping, optional brief English as third line (also popups), fast open-source local processing and context-based handling of ambiguous readings. Search the world's information, including webpages, images, videos and more. Google has many special features to help you find exactly what you're looking for. Save time, stay connected. From simple navigation to voicemail transcription, Voice makes it easier than ever to save time while staying connected.

GooglePinyinInstaller.exe -s

This is tested on version 2.7 on a Windows 7 machine, however, it will not show in Programs and Features (Add/Remove program). To add an entry to it, you need the below registry:

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINESOFTWAREMicrosoftWindowsCurrentVersionUninstallGooglePinyin2]
“DisplayName”=”谷歌拼音输入法 2.7”
“UninstallString”=”C:Program Files (x86)GoogleGoogle Pinyin 2GooglePinyinUninstaller.exe -s”
“DisplayIcon”=”C:WindowsSysWOW64GooglePinyin2.ime”
“Publisher”=”Google Inc.”

Update (11 May 2010): Josh (in the comments below) alerted me to a shortcut to switch between traditional and simplified input, just use ctrl+shift+t to switch. Thanks Josh

I got a request from Rebecca, who found a comment that I had made about installing the Google Pinyin tool. She emailed me and asked me to show her how to change the google input method tool to Traditional Chinese. I’m chuffed someone asked so nicely. So here you go…

For those who want it go to http://tools.google.com/pinyin/ and click on the “big blue button” to download it.

Install it the usual way. And continue when finished.

For Newer Windows

Google Pinyin Installer Free

From the language bar, click the “EN”, then select “Chinese (Simplified, PRC)” to change the language.

The Google Pinyin toolbar will appear.

Click the menu button.

Then click the settings menu item shown below.

Select the fifth tab then make sure the second option (for Traditional Chinese) is checked.

Click “Apply” to apply the changes, or “OK” to apply and exit the options page.

For Windows XP

From the language bar, click the “EN”, then select “Chinese (PRC)” to change the language.

Google Pinyin For Windows

The Google language bar appears.

Right click the blue ball part of the Google bar, and select the item shown.

Google Chinese Pinyin Input Download

Select the fourth tab.

Check the “Traditional Chinese” option.

Click “Apply” to apply the changes, or “OK” to apply and exit the options page.

All done!

Download Google Pinyin

All the characters that appear when using the tool should now be Traditional Chinese. The characters in all the menus and options remain in Simplified Chinese.

Rebecca, enjoy.