It didn't take long to evolve meta-search services that fork off tasks to any number of other search engines. (Parasites, one might say. The meta-search page gets credit for work done by others.) The invoked engines are usually those with similar search capabilities: phrase search, boolean search, required or excluded terms, etc., but users typically specify only the simplest search syntax. These are time-limited and count-limited searches, so don't expect complete retrieval.

It's tough for a second-level engine to rank results, as it doesn't have page information available. Still, an engine-by-engine display can be a great way to compare results of different services. Once you find a good service, try it for deeper searches. Some useful meta-searchers:

The Cyber 411 parallel engine invokes 15 of the top search engines, presenting results separately or merged. You can add a Cyber 411 search form to your own Web page. . (Searches take/are allowed less than five seconds.)

Webtaxi offers sequential and parallel searching via international and regional search engines. . (The interface is designed to stay active at the top of your browser window, so you don't have to branch to a bookmarked page.)

Dogpile will query up to 25 search engines and archives for the top 10 matches, displaying each batch separately. Proximity search is permitted, for engines that support it. After checking a few engines, Dogpile asks if you want to continue with additional ones. You can control the indexes searched and their order. . [Leonard Foner , 05Aug97.]

MetaFind, from the same company as Dogpile, searches nine web indexes (that all allow OR syntax), then merges the hits alphabetically. .

"Searches" uses a MetaCrawler engine to invoke seven search engines. .

ProFusion uses up to nine search engines, then removes duplicate hits and optionally checks for dead links. It can also run repeated searches to alert you to changes. . (I was unimpressed with the relevance ranking.)

USE IT!, the "Unified Search Engine for Internet," is a nice parallel searcher with an English, Italian, or French interface. You can also download HTML code to add USE IT! parallel search to your own Web pages. .

Bingo! is an English/Japanese applet that invokes up to 12 engines. . (Very slow site.)

Webmate Personal Search Agent (in Java) searches ten engines in parallel, then uses feedback on which sites are of interest to you. .

LiveAgent is a personal agent builder available in beta for downloading. It comes with a prerecorded Java agent called SearchAgent, able to query several search engines in parallel and return a ranked, sorted listing of sites with the duplicates deleted. Filtering specifics are determined by the user. .

W3QS supports a declarative query language called W3QL, plus several "friendly" querying interfaces to Web search engines. Full page content can be screened by PERL filters (including context-sensitive variables). Queries can be entered for future submission, e.g., at time intervals while the user is off-line. . [Oded Shmueli , dbworld, 23May97.]

EchoSearch for Windows 95/NT and PowerPC Mac queries multiple engines and merges the results. Able to download found pages and use NLP for ranking. 15-day free evaluation, then $50. .

WebFerret 1.10 for Windows 95/NT lets you perform simultaneous searches using your own list of search engines. You can limit the total number and type of search results that are returned. Free, or $14 without advertising. . (The NetFerret suite for $30 contains utilities for searching email, files, news, IRC directories, phone numbers, etc.)

Quarterdeck's WebCompass is a sophisticated commercial product (with free trial version) that queries multiple engines, sorts and cleans the results, and saves relevant info for later use. It includes a thesaurus and relational database of search terms. Windows 3.51 or 95. .

-- Ken