I really like the star fissure--both visually and thematically. I thought that the way it tied together the beginning of Myst with the end of Riven was brilliant :)
(Ideally I'd like to include more discussion in my link roundups, but I'm fighting a cold right now and would rather get things moving than wait until I have the brainpower to come up with more eloquent things to say.)
Comm business: I'm putting some links to good fan resources like MystLore in the links list of this community. I've tweaked the style for the comm a bit as well--please let me know if there's anything that looks weird on someone's computer. Oh, and the comm now has 6 Myst/Riven icons--feel free to use them yourself (with credit to the original creator).