I have a work email account which I access via a range of different mail clients depending on what device and where I am. We use an IMAP4 based system so I use Thunderbird, pine, AppleMail(iPad) and K9 mail Android.

We get a quota and I live in the quota. I never create folders which are local, preferring to keep all my mail on the server accessible from anywhere. Its company mail.

When I needed an email account for me personal use some 10 or so years ago I went with googlemail and have stuck with them. I think its a good idea to have an email account independent of your ISP. Its painful to switch across and notify everyone, but in the long run I think its a good thing. That way if you decide to change ISP, you don't have to go through all the pain each time.

Gmail and Yahoo are large well established candidates and some larger ISP's OEM the yahoo and google systems anyway.

My vote for gmail is based on usability - it really is the best email system I have used since I started using unix command mail in 1984.

It does all the usual things but the strength of the search is key. It doesn't have folders per se, but uses labels which are more powerful (one mail can have multiple labels). However search underpins it. I just have one big inbox in which I sub search to find things. I personally find this much easier than using folders. Sure most email clients have some kind of search, but this typically relies on downloading mail to be indexed locally.

I have never been a user of Outlook so I'm not sure what the differences are, but gmail seems to have everything I need and more. Of course it does support IMAP4 so I could access it from a IMAP4 client (AppleMail, Outlook) and that would work fine, but I would loose that server-side search capability which I find essential.

I have server-side filters set up to sort and auto-trash some mail and the benefit is that these are run on the server when the mail arrives, so no matter which client I use to access the mail, its been sorted. many mail desktop clients have filters but they only 'fire' when that client accesses the account, so not as good for mobile or roaming use.

Sure my Trash is full of spam and I get the occasional phising or spma mail in my Inbox, but actually its fairly rare, . I'm a good citizen at reporting spam/phishing through gmail so maybe that helps.

I don't backup my gmail, maybe I should , and I could if I used thunderbird or applemail as a client. A compromise might be to label some mail as 'Valuable' which flags that up as a singleIMAP4 foder which I could then backup.

I can even use pine against gmail - pine is an old school "green screen" terminal mail client, but an extremely functional one, and sometimes I take it for a spin, and always enjoy how fast I can plough through email with it.

So my vote is for gmail