Ive used:
elm, Thunderbird, Outlook, Outlook Express (mac and PC versions), Entourage, Zimbra Desktop, Eudora since v1.5.1, OS X Mail, Mailsmith, at least half a dozen various email interfaces on BBS's (CNet Amiga, WWIV, Hermes II, NovaLink Pro, Wildcat, TBBS, Searchlight, White Knight/Red Ryder, FirstClass, TeleFinder, RIPscrip-interfaces, various QWK offline readers, others I can't recall), and of course GMail, Hotmail, and Yahoo. I suppose to be complete I should add to the list CompuServe's command line and GUI interfaces as well as (I'm embarrassed to say it) AOL's client and the old Prodigy system.

Out of all of those, in my opinion GMail has the best interface. Why?

-You almost never have to take your hands off the keyboard. If you want to open a message in a new window, or compose one in a new window, just hold down shift and press the shortcut. With Labs you can also move to labels using the "gl" shortcut.

-Speaking of single-key shortcuts, I love GMail's. Im a vi guy not an emacs guy so maybe that explains why I like single-key shortcuts. I know I can always use some multi-key combination in all of the other above-mentioned applications, but I find single-key superior for some reason. That's just my preference.

-GMail's Search function. Wonderful. Look for anything remotely like this in the GUI clients available on Mac and Windows right now, about the only thing that comes close is Instant Search in Outlook 2007. Even Spotlight's performance is lackluster. When I tested GMail Offline on my old PowerBook G4, it actually finds email faster than spotlight searching Entourage's catalogs. This was a completely subjective test but it looks to be true.

About all that's keeping me from dumping my current mail app and moving completely to GMail to consolidate all of my email accounts into a single inbox are two things:

-That annoying "(sent by account@gmail.com)" GMail appends in the From: header with every message sent using a different from address. Yes I know I can add Google Docs to my domain name, but even then it will add (sent by account@gdocsuser.com) which is just as annoying.

-Multiple signatures linked to specific From: addresses. I don't want to use Scriptmonkey hacks to do this, since that just ties me down to an app only usable on my own laptop.

Incidentally, GMail Offline seems to work fine on Safari 3.2.1 running under German localization, as well as Firefox under German localization.

...including the ability to switch power profiles from the power menu icon. Now if you want to temporarily switch from Better Performance to Better Battery Life, you have to open System Preferences.

You already said they are avid readers - challenge them. Just because it might seem dry or too political when you look at it as a parent doesnt mean they wont like it or get something out of it. If they don't like it, they won't read it, but whatever you do don't decide not to bring something because you think they wont like it. Imagine the disaster if they hate everything you bring because you tried to dumb it down too much.

When I was younger, I read LOTR in 4th-5th grade, had an abortive attempt at reading Neuromancer in 6th grade (I loved the old Interplay game so much I made myself try reading the novel again 6 months later. it turned out to be the first book I read under a day). One of my best memories as a child was emailing Orson Scott Card on the old Prodigy network after I read Ender's Game. He encouraged me to read Speaker, albeit with the 'its a bit slower-paced' warning. Turned out I loved Speaker, and my father, who recommended Ender's Game to me, couldnt care less for Speaker.

All of these books, we read when we were kids or teenagers. They shaped our understanding of the world but also helped us formulate our own. Let your kids do the same. Thats the beauty of a book.