Short for "Opera
6 Search.ini Editor", an incredibly useful, free utility (for Opera
users) developed by Andrzej Olaczek and found at:
Using this utility, you can easily delete any of Opera's built-in searches that you don't use. You can also choose from a number of predefined search engines to add into your search.ini file, or create your own definitions.
Once you're done modifying your custom set of search engines, simply click Save and restart your Opera browser. You can view your list of search engines and assigned keywords at any time in the Opera's Preferences->Search. To quickly launch a given search for "warchalking", you can then simply hit F2 (Go to page) and type "KEYWORD warchalking".
For a list of other search engine definition strings, check out my writeup on Opera browser.