I'm currently using the following services:
1) DNSMadeEasy (
http://www.dnsmadeeasy.com) is an excellent DNS hosting company and charges me around £17 a year for hosting 50 DNS zones with them.
2) NamesCo (
http://www.names.co.uk) for domain registration. More expensive than 123-reg, but far more competent.
3) Google Apps For Your Domain (
http://www.google.com/a) which gives you Gmail, Google Calendar, Google Pages and Google Talk for your own domain name. Still in beta, and you're not guaranteed to be approved straight away, but if you are, is one of the best ways of getting webmail, POP3 and SMTP access wherever you are. It'll be free for beta testers when the product comes out of beta. You'll get a minimum of 25 accounts and it can handle aliases/catch-all (if need be) and lots of other good stuff.
4) An alternative to free webmail (but not domain based) is Inbox.com (
http://www.inbox.com) which gives you a 5Gb mailbox and is quite nippy. Also provides free online storage for files too.
5) Box.net (
http://www.box.net) is a good system for keeping frequently accessed files between PCs or for filing stuff that you want to keep in case your hard drive fails. Very intuative Flash interface and requires only a web browser.
M.