Twentyman, Jessica. Letting go of email. Infoconomy. 8 Dec. 2004.

Some good info in here. Reference to Gartner estimate of e-mail management costs in large companies around $1,600/user/year. Emphasis placed on achieving efficiency in archival rather than simple brute-force archive-all methodologies. Also mention of the Commercial Litigators' Forum (CLF) that seems heavily engaged in e-discovery.