Here's a wonderful concept. Yeah, the execution's pretty rock-bottom, but it doesn't stop it from being a great idea. It's The Forbidden City in China, presented as a free MMO, of sorts. No grinding the Terracotta army or hiding dragons here though - it's strictly a tourism/educational toy. An Oriental Second Life with tour guides and no unicorn-humping, in a way.
This being the Forbidden City and not the Lego city, there's no construction, and barely any interaction beyond navigation - it's simply sight-seeing and information-gathering, but you're able to wander and stare at your leisure. It looks desperately low-rent, but does nevertheless convey a certain sense of grandeur: it's certainly a huge step on from the sort of rubbish 'interactive CD-ROMs' you tend to find in tourist gift shops.
There are a few attempts at something braver, too. Have an explore and you'll stumble across a couple of remarkably odd mini-games - like training crickets to fight. All in the name of historical authenticity and too low-fidelity to be horrific, but God. Quite the departure from staring at Qing era architecture.
The really interesting element is the MMO side of it. You're visiting in real-time, alongside anyone else who happens to log in. You can chat, you can join tours together - an MMO party designed for learning, not experience points - or you can even host a tour yourself. Again: a wonderful idea. So, it's a shame it looks like Tomb Raider 1, but with the right technology a project like this could be an incredible tool for schools and for penniless tourists alike. I love the idea of whiling away a bored Sunday roaming around a high-detail online Taj Mahal or Chicago skyline. Clearly nothing like the same as being there, but as a shortcut to getting a sense of architectural wonders, an MMO system seems ideal. Google maps, the MMO? Oooh.
Oh, and it's free. But please, don't complain at me about the graphics and the interface: again, it's the concept rather than the execution that I'm so intrigued by.