1. A method for displaying an email conversation across folders comprising: grouping email messages into conversations, where the grouping is performed independent of folders in which the messages reside, thereby enabling conversations to span multiple folders; and displaying at least one of the conversations, the at least one of the conversations including a plurality of messages, where, for each of the plurality of messages in the at least one displayed conversation, a folder associated with each of the plurality of messages is identified, wherein grouping email messages into conversations comprises: determining from a subject line of an incoming message whether the incoming message is a follow-up message; in response to the incoming message not being a follow-up message, creating an open conversation based on the subject line of the incoming message and associating the incoming message with the created open conversation; in response to the incoming message being a follow-up message, normalizing the subject line of the incoming message and determining whether or not an open conversation exists for the normalized subject line; in response to an open conversation not existing for the normalized subject line, creating a new open conversation for the normalized subject line and associating the incoming message with the new open conversation; and in response to an open conversation existing for the normalized subject line, associating the incoming message with the existing open conversation, and wherein determining whether or not an open conversation exists for a normalized subject line comprises: in response to there being an open conversation corresponding to the normalized subject line, determining whether or not the a last-received message in the open conversation was received before a certain date; in response to determining that the last-received message was received before the certain date, closing the open conversation and determining that an open conversation does not exist for the normalized subject line; in response to determining that the last-received message was received after the certain date, comparing header information in the incoming message with header information in the last received message in the open conversation to determine whether similarities in the header information indicates the incoming message and the last-received message are related; in response to determining the incoming message and the last-received message in the open conversation are related, determining that an open conversation exists for the normalized subject line; and in response to determining that the incoming message and the last received message in the open conversation are not related, closing the open conversation and determining that an open conversation does not exist for the normalized subject line.
1. A method for displaying an email conversation across folders comprising: grouping email messages into conversations, where the grouping is performed independent of folders in which the messages reside, thereby enabling conversations to span multiple folders; and displaying at least one of the conversations, the at least one of the conversations including a plurality of messages, where, for each of the plurality of messages in the at least one displayed conversation, a folder associated with each of the plurality of messages is identified, wherein grouping email messages into conversations comprises: determining from a subject line of an incoming message whether the incoming message is a follow-up message; in response to the incoming message not being a follow-up message, creating an open conversation based on the subject line of the incoming message and associating the incoming message with the created open conversation; in response to the incoming message being a follow-up message, normalizing the subject line of the incoming message and determining whether or not an open conversation exists for the normalized subject line; in response to an open conversation not existing for the normalized subject line, creating a new open conversation for the normalized subject line and associating the incoming message with the new open conversation; and in response to an open conversation existing for the normalized subject line, associating the incoming message with the existing open conversation, and wherein determining whether or not an open conversation exists for a normalized subject line comprises: in response to there being an open conversation corresponding to the normalized subject line, determining whether or not the a last-received message in the open conversation was received before a certain date; in response to determining that the last-received message was received before the certain date, closing the open conversation and determining that an open conversation does not exist for the normalized subject line; in response to determining that the last-received message was received after the certain date, comparing header information in the incoming message with header information in the last received message in the open conversation to determine whether similarities in the header information indicates the incoming message and the last-received message are related; in response to determining the incoming message and the last-received message in the open conversation are related, determining that an open conversation exists for the normalized subject line; and in response to determining that the incoming message and the last received message in the open conversation are not related, closing the open conversation and determining that an open conversation does not exist for the normalized subject line. 4. The method of claim 1 , wherein the display of the at least one conversation includes all of the plurality of messages in the at least one conversation, regardless of folders in which the plurality of messages reside.