Top 50 Second-Level Domain Names

 1146825 aol.com                     134422 home.com
  955215 ans.net                     134152 or.us
  677596 af.mil                      125169 netcom.com
  649687 ac.uk                       118453 co.jp
  601225 uu.net                      114992 umich.edu
  491517 co.uk                       111813 nasa.gov
  485529 or.jp                       109657 ac.nz
  378249 ac.jp                       104202 bc.ca
  314885 edu.au                       99309 dialsprint.net
  293972 navy.mil                     98303 gov.au
  290498 psi.net                      95353 boeing.com
  259013 bbn.com                      93147 com.br
  251850 ibm.net                      92045 intel.com
  249862 hinet.net                    89893 autonet.net
  249406 ca.us                        89297 tx.us
  248088 ne.jp                        89082 ad.jp
  228889 att.net                      88068 co.kr
  201303 airdata.net                  85270 pacbell.com
  195834 cdc.com                      85144 bellsouth.net
  190937 army.mil                     84300 compuserve.com
  189533 dec.com                      79544 berkeley.edu
  157878 com.au                       78428 gsa.gov
  157461 mn.us                        77997 co.za
  145507 net.au                       75845 baynetworks.com
  135926 hp.com                       75432 cisco.com

Internet Domain Survey