Search Gmail in Firefox
Go to this site and install Gmail Search.
Search Gmail in Internet Explorer
Download the new Google Toolbar 4.
Search Gmail in Opera
Go to Help/About Opera, copy the folder location for "Opera Profile", open it. Edit search.ini, go to one of the entries [Search Engine n] (for example, [Search Engine 2]) and replace the first two lines with:
More about Gmail:
Gmail Chat in Opera
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