21. A computer-implemented method comprising the steps of: receiving, at a client node, a not-yet-submitted search query from a user; prior to receiving an indication from the user that the not-yet-submitted search query is completely formed, determining, at the client node, whether the not-yet-submitted search query (a) includes a character in a set consisting of non-alphanumeric characters or (b) matches a phrase in a dictionary of pre-defined phrases; and sending the not-yet-submitted search query from the client node to a search engine, to perform a search based on the not-yet-submitted search query, only after determining, at the client node, that the not-yet-submitted search query includes a character in the set or matches a phrase in the dictionary; wherein the not-yet-submitted query is sent over a network to the search engine; wherein the search engine, prior to receiving an indication from the client node that the not-yet submitted search query is completely formed, determines: a predicted search query by predicting what the not-yet-submitted search query will be when completed, and based on the predicted search query, an alternative search query that differs from the predicted search query; receiving, at the client node and from the search engine, the alternative search query; wherein the steps are performed on one or more computing devices.
21. A computer-implemented method comprising the steps of: receiving, at a client node, a not-yet-submitted search query from a user; prior to receiving an indication from the user that the not-yet-submitted search query is completely formed, determining, at the client node, whether the not-yet-submitted search query (a) includes a character in a set consisting of non-alphanumeric characters or (b) matches a phrase in a dictionary of pre-defined phrases; and sending the not-yet-submitted search query from the client node to a search engine, to perform a search based on the not-yet-submitted search query, only after determining, at the client node, that the not-yet-submitted search query includes a character in the set or matches a phrase in the dictionary; wherein the not-yet-submitted query is sent over a network to the search engine; wherein the search engine, prior to receiving an indication from the client node that the not-yet submitted search query is completely formed, determines: a predicted search query by predicting what the not-yet-submitted search query will be when completed, and based on the predicted search query, an alternative search query that differs from the predicted search query; receiving, at the client node and from the search engine, the alternative search query; wherein the steps are performed on one or more computing devices. 28. A computer-readable storage medium storing instructions which, when executed by one or more processors, cause the performance of the method recited in claim 21 .