Alta Vista

• link:http://foo.bar.com/ to search for links to a URL
• url:http://foo.bar.com/ to search for pages in a URL
• from:, subject:, and newsgroups: restrictions can be used in usenet searches.
• Put a +plus sign in front of words that must be in the results.
• Put a -minus sign in front of words that must not be in the results.
• Enclose words "in quotes" to treat them like a phrase
• Asterisk: Use psiloc*in to search for psilocybin and psilocin for instance.
• Sample: "blue star" +lsd +tattoo -bodyart

Infoseek Guide

• Capitalizing adjacent names causes Infoseek to treat the words as a single name. (Use commas to separate different names, e.g. Timothy Leary, Stan Grof.
• "quotation marks" denote words that must appear next to each other. (e.g. "blotter acid").
• hyphenating-words indicates that the words must appear within one word of each other.
• [use brackets] to find words that appear within 100 words of each other.
• Put a +plus sign in front of words that must be in the results.
• Put a -minus sign in front of words that must not be in the results.

Deja News

• Search usenet news (e.g. rec.drugs.chemistry)

Lycos

• Use AND and/or OR

Excite

• Search terms treated as a "fuzzy AND" -- an OR with priority to ANDs.
• Use a + sign in front of a word to require that word in the search results.
• Use a - sign in front of a word to forbid that word in the search results.
• Use AND, OR, NOT, AND NOT, and parentheses to restrict the search.

MetaCrawler

• Use (parenthesis) to mark a collection of words as a phrase where the words must appear relatively close together.
• Put a +plus sign in front of words that must be in the results.
• Put a -minus sign in front of words that must not be in the results.

Magellan

• Rates and reviews sites according to content and presentation.

NlightN

• Default is "AND"
• Use & (AND), | (OR) or ^ (NOT) to restrict search.
• Use (parenthesis) to eliminate ambiguity in boolean expressions.
• "Within field" means that the search requirements must be met in a "field" (e.g. Author, Subject, or Title).
• "Across fields" returns records where the search requirements are met in the record as a whole. (Currently works only with the "Databases" option).
• "Alphabetically" will return records containing the keyword selected, and also keywords which are stored alphabetically close to the keyword (e.g. "psychedelic" -> "psychedelics," "psychedelically")
• "Universe" searches everything, "Databases" searches only NlightN's proprietary databases.

Open Text Index

WebCrawler

• Use AND, OR and NOT operators.
• Use (parenthesis) to remove ambiguity from search operators (e.g. McKenna AND (Dennis OR Terence)).
• Use NEAR/# to find two keywords within a certain number of words of each other (e.g. lsd NEAR/20 tattoo or alkaloid NEAR/25 extraction)
• Use ADJ to find keywords that appear together in a specific order (e.g. cannabis ADJ indica)
• Use "quotes" to denote a phrase (e.g. "self-transforming machine elves").

Yahoo!

• The yellow pages of the web.

Other search engines: