whois archivd.com

   Domain servers in listed order:
      NS1.WORLDWIDEDNS.NET
      DNS0.MTGSY.COM
      NS2.WORLDWIDEDNS.NET
      DNS1.NAME-S.NET
      NS3.WORLDWIDEDNS.NET
      DNS3.MTGSY.COM

The only other smallbiz-grade service I've used is DNSPark. They are decent but their management interface is painful and has not changed in 7 years (!).

moved to zerigo this spring: http://www.zerigo.com/

been happy with it, and they have an easy to use API so if you are doing ~cloud~ things, you can script adding DNS entries etc quite easily from most programing languages.