Well, another year goes by and I'm coming up empty-handed on this one. I know a lot of y'all were also interested in this niche at some point, so let me run this past you and see if I missed any major products.
Almost 10 years ago now, I got my grandmother an iOpener. The default install had its quirks, but it was capable enough at the time and pretty resilient -- at worst, pull the plug and let it do a cold boot. She gave up on it a few years ago when the embedded copy of Voyager got too dated to render most sites and the quantity of "offensive" spam coming through ruined her e-mail experience. (Sadly, Earthlink took over the accounts but never offered server-side spam filtering. In fact, in that chunk of the era, Earthlink's only spam solution was an Outlook or IE plugin..)
So, what ever happened to the "Internet Appliance?" It's obvious that "never support anyone over 30" is a rule in tech, but the short list of products is still depressing:
* Eee box:
They gave up and shipped these with Windows in the US, with one of those "Press F1 to get to a Linux image in firmware" distros. First you pay the Microsoft tax, and then I'm not confident that the "EZ-BIOS" permits basic things, like saving bookmarks. One wrong move and you're in Windows anyway.
* Eee laptop / Netbooks in general:
Cute idea. Well-executed. Trendy. But what sadist gives a device with a 7" display and miniature keyboard to someone with arthritis and reading glasses?
* CherryPal:
Not sure if these are actually on the market yet. MIPS platform would seem to suggest no Flash out of the box, and as much as I share the world's pain on that, it's the "innocent victims" who won't be able to view YouTube.
* gOS "Cloud" / Everex gPC:
Almost the right idea, but as far as I can tell, still a failure of execution. FAQs talk about working around missing artwork for, e.g., the volume control applet in the gnome-panel... and also about modifying the sources.list so that the installation won't automatically offer to break itself ("An upgrade is available!") every 6 months. Apparently the gOS customizations were just written over a Ubuntu image and aren't packaged to permit a dist-upgrade? Fail.
* Shuttle KPC:
Another 'almost,' the Linux models with Foresight would seem to have problems equivalent to Ubuntu below. Reviews also suggest that Shuttle found the loudest fans in the world for these units.
* Nokia 'tablets':
Well-thought out as Linux products go, but incredibly tiny and require a GSM data plan.
* Misc. x86 CherryPal-like devices:
Invariably ship with something like Puppy Linux or cut-down Ubuntu. These all seem to be designed for, and might make sense for, schools, libraries, or somewhere with at least the vestiges of an IT department. The hardware exists but the software invariably tries to be more than just a browser -- with the complexity and configuration details that entails. Recovery/reset-to-defaults procedures are geared for IT people. Little guarantee that the 'embedded Ubuntu' products don't suffer something like the gOS problem: Accept updates, immediately run out of space on the GB or two of flash, require professional attention.
* Wii, PS3:
The only way to get an embedded browser hooked up to a large display off-the-shelf? Silly, if almost plausible. Would require tracking down keyboard peripherals separately. I haven't gotten around to figuring out if the Wii actually comes with Opera or how they're handling that.
* Ubuntu itself:
I'm working with it every day. On a good day it's certainly acceptable for someone who wants a "computer" and all that entails, but the level of complexity is still far beyond a WebTV. Itself at risk for breakage on update depending what X.org has been doing in the past 6 months. Still disappointingly unheard-of in Small Town, USA; when "continuing education" places start offering introductory courses things will improve, but that hasn't happened yet.
So... maybe I'm getting cynical and crochety here myself. Having gone through all of the above, the only option that seems approximately tenable would be an iMac, and then only to the extent that it has a snowball's chance of launching a browser out of the dock on most days and can be dragged to the hipsters at the mall when something goes wrong.
Did I miss anything? Anyone want to commiserate?