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To change the default request page, edit your local.ini file adding a section like:
[httpd_global_handlers]
/ = {couch_httpd, send_redirect, "/blogdb/_design/sofa/_list/index/recent-posts?descending=true&limit=5"}When you goto http://127.0.0.1:5984/ instead of the usual version information, it will redirect to the page you specified.
For more advanced modifications to url handling see power http handling.