Searching may be done by string, by quoted string, or with wildcards. Publicly Accessible Mailing Lists by Stephanie de Silva is indexed by name and by subject keyword. It is not searchable, but list entries have one or more of 545 keywords assigned to them as descriptors. List entries contain a short description of the list's purpose and information on how to subscribe. Descriptions of purpose range from a sentence to a paragraph in length.
Some entries have a link to an external site.
All entries have alphabetic links to previous and next entries and most have additional subject links. The actual index grouping appears to be done automatically. Search List of Lists is a searchable list of e-mail lists that is maintained by Vivian Neou. The entry page also plugs her book on e-mail lists. Pitsco's Launch to Educational Listservs includes lists primarily of interest to academic communities.