AGN Domain Name Services
   Registration of alternative .earth, .usa, and .z top level domains.
   http://www.adns.net/

Domain Name Systems
   Alternate Registry of the .xxx and .sex domains.
   http://www.domainnamesystems.com

IPv8 G:S Numbers and TLDs
   Listing of proposed alternate TLDs in the 128-bit DNS supported by IPv8. These TLDs are NOT supported by ICANN.
   http://www.ntia.doc.gov/ntiahome/domainname/130dftmail/unir.txt

Mobile Domain Names Registrar
   MobileTLD.com registers domain names for Wireless Internet use in 9 zones (.mobile, .imode, .mmode, .palm, .wap, .hdml, .3g, .wire, .pda) and 340 second level spaces.
   http://www.mobiletld.com

New.net
   Website of one of the leading alternate roots. Includes a download of a plug-in that will allow users to utilize the alternate roots provided. The website also includes registration services.
   http://www.new.net

OpenNIC
   Completely open and democratically managed root domainname system.
   http://www.opennic.unrated.net/