Going, going, gone...
Domain Names are usually assigned on a first come first served basis and they're running out fast. You pay a fee to the registry for the maintenance of the database and a fee to the company carrying out the registration and maintaining your entry.
Some companies also charge for administering their DNS system or for assigning a name to a new ISP. Renewing a Domain can sometimes cost more than the original registration. Others just take your first payment then forget about you, you have to pay the on-going fee direct to the registry at the full rate!
Arrowhead discount the registry rate and only charge a one time fee for the registration of a domain. All database changes are carried out free of charge, the only future charges you will pay are for discounted registry fees to maintain your Domain registration.