First things first:

• Zeitgeist is essentially fashion for ideas. See a discussion about it on Wikipedia.
• Why the name ? Because when this idea was first discussed, someone on Drupal (chx, I think) said 'Oooh, a Zeitgeist', and I liked it.

• Log searches with their timestamp
• A customizable drupal block with the 'n' most recent searches. Since v1.4, 'n' is settable
• A customizable drupal block with the 'm' most popular node searches during the current month. Since v1.5, 'm' is settable
• 4.7beta6-compatible

• A page displaying the most requested searches over a given time span
• A RSS feed tracking all searches
• A periodic (weekly) summary of the top queries, by email to the site admin
• A setting to include queries by UID=1 or not

• Table 'zeitgeist' contains the search log
• Variables:
  • zeitgeist_history: the duration entries are kept in the log table
  • zeitgeist_latest_count: the number of entries to be displayed in the “recent searches” block
  • zeitgeist_latest_info; the customized info of the “recent searches” block (in the blocks list)
  • zeitgeist_latest_title: the customized title of the “recent searches” block (when displayed)
  • In zeitgeist_latest_info and zeitgeist_latest_title, the string %count can be used to insert the value of zeitgeist_latest_count