I use the sparrow Mac client and love it. I keep it on the top left of my 27" iMac screen about and it's roughly 350px wide by half the screen tall. Twitter s

I use the sparrow Mac client and love it. I keep it on the top left of my 27" iMac screen about and it's roughly 350px wide by half the screen tall. Twitter sits underneath it at the same width/height. It only has 2 email accounts linked to it (work and personal) and they are both gmail. It's always on and always there. I prefer it to the gmail web app because I can keep it visible and it's a couple of keyboard shortcuts away to read and send email, can keep me logged in to both accounts simultaneously without having to "hack" gmail with an incognito window or two separate browsers, and...it's not a web app. Oh, and the interface is so much simpler than gmail and I confess to not using labels or tags or filters or anything "advanced" in gmail so it is perfect for me. I'm personally not so bothered that they aren't going to continue improving it because it does everything I need it to do, but for me it was definitely worth the $10 I paid for it and it fits my workflow/screen layout much much better than a web app would.