Simplest way to have a mail server for my domain

I have a domain name registered and I want to be able to send and receive mail for some mail addresses @ mydomain. I'm talking about a small number of addresses, and small mail volumes (but I would like to be able to scale if needed).

I guess there are at least three options:

1. Run a mail gateway myself (which I am well familiar with, but would prefer to avoid the hassle)
2. Paying a web hosting company to run a gateway/host my mail accounts for me.
3. Use a hosted email gateway services like AuthSMTP.

So my question is: what have you found to be the simplest and cheapest option? Are there other options to consider?

Thanks for the responses - overwhelming support for GoogleApps. I've tested this out, and as claimed by many - it rocks.

Best Solution - GoogleApps

Here's a summary of what I setup and how:

1. Signed-up at GoogleApps. The "Standard Edition" is just fine for me to get email service.
   1. Next step is to validate your domain ownership by either posting a special file on a website running at the domain, or insert a special CNAME record in your dns entry
   2. Once the domain is validated, the chat, docs, calendar and sites features will be active.
   3. To enable Email, also need to configure the MX records for your domain
2. I have a domain registered at http://whois.com, but it was just pointing to a domain parking page, so I first had to add the "Managed DNS" service to my whois account and change my nameservers from the domain-parking addresses to the whois.com nameservers. Seemed to take about a day for this to propagate properly before I could proceed.
3. I added the special CNAME entry (as prompted by google) and told google apps to try and verify my domain ownership
4. Then simply had to add the MX records as prompted by google.
5. Presto - I'm sending and receiving mail from my own domain. Total cost - about USD3.88 for the DNS service I am using.

From stackoverflow tardate

• I believe you can get Google Mail for your domain for free via Google Apps. This includes IMAP support, if you want to use desktop mail clients. I haven't used the service, myself, so I can only assume it's as easy as defining Google as your MX after you sign up.

  Stefan Koenig : I'm using it for many of my Domains and even recommend it to my customers. Also I'm managing some Email-Servers, I'm considering moving them to Google, since I think they handle my mail far better than I ever will.

  lordscarlet : Google hosted mail is fantastic.
  From Adam Backstrom

• Well, as you say, it's a bit of a hassle to setup a mail gateway, so my suggestion would be to set up Google Apps with your domain. It is pretty straight-forward, easy to setup and most people already use/know google mail that they can easily make the transition.

  From Christian P.

• Google Apps, all the way. Simple to set up and oodles more reliable than any other mail hosting I've ever used. Free for a surprisingly large number of users & storage; cheap as chips thereafter.

  From moobaa

• While it's a lot of fun to setup your own e-mail, it just doesn't pay to do it. Even purchased hosting tends to be cheaper than what the electricity alone would cost to do at home...

  From Brian Knoblauch