Our telephone line needs fixing. Every time it rains we lose the internet. The phone company guy said he found the tell-tale evidence of mice nibbling the cables. We've called an electrician. But this experience, my annual trips to India, and the occasional slowness of Gmail's servers, have convinced me I need to become more independent of a constant online connection. In addition, while Gmail is very convenient, I'm beginning to be irked by that convenience. So although I've been such an enthusiastic proponent of Gmail, and have been responsible for getting numerous people in our offices off mail clients and onto webmail, now I'm going back.
For some time I've been handling my home email through Opera's mail client through imap. I got the idea of doing the same with my work email, which is much busier. At first I tried Thunderbird, but couldn't get used to it (even after tweaking with the conversation view plugin and calendar sync). Also, from the days when I did use Thunderbird, I have at least one bad memory of its file system. It just doesn't seem safe to have all messages in a single corruptible file. So I looked for other solutions.
I've heard lots of good reviews of Mutt, and was able to fairly quickly set this up. Just as everybody says, Mutt is amazing. But I think it would take me a while to get used to working in a console. Further, since much of my email is html, or needs translation, I'm still going to end up going back into a browser. I also noticed that the Hebrew subject lines get reversed (from left to right). I do like the fact that Mutt's Mail dir file system is equally accessible to Kmail and Evolution, among others.
Eventually, I've just added another account to my Opera mail client. That was just in time for the upgrade Opera have just made to the appearance of their mail client (though I've been enjoying the change in Beta for some time now). But also before the upgrade, Opera has had special settings for Gmail (taking into consideration its labeling system, and other features), so it's about as good as an offline client could be. Opera also has a really fast and capable search, and various other unique features.
The advantage of using Opera is also that I can have my offline imap email open in one tag, and still open other Google applications like the calendar in another tab. That's not exactly cheating, since I'm not as dependent upon these applications as upon email.
So now I've simplified my system so that instead of using multiple browsers and programs, I can let Opera handle most of my communications needs: public and private email, newsfeeds and general surfing. Although I'm offline, Google Talk is still available through Pidgen. I've enabled privacy controls to prevent Google and other companies from tracking me.
It's too early to say how offline email will work for me, but so far it feels good.
PS: Someone might wonder why not simply to use Google's native offline client available in Chrome. Unfortunately, it isn't configurable at all. It's possible to download about a week's email and then important messages from the past. But I frequently need to check back through my entire message store. Chrome's offline gmail client seems to be intended strictly for casual use or internet emergencies. Google would obviously prefer for us to use their online client and yesterday they added new social features (which won't necessarily please everybody).