it would probably be intrusive...

...but sometimes I think it would be cool if journalling sites had a function to "suggest me a new journal to read" not a random one, but a suggestion based on your current subscriptions, interests, maybe on some kind of other fuzzy, internal data-mining (the aforementioned "intrusive" part). I'm not sure how these things work, but like what Amazon does when it suggests books to you (sometimes they even suggest me interesting things, though that one is hit and miss, even though I actually tried to refine it manually) or that online music thing, Pandora?, that tries to guess what your tastes music are (that wasn't bad, though I couldn't use it for long, because eventually these location blocks happened). Anyway, something more advanced than the "popular among your friends" feature that LJ offered (offers? I can never really find that on the site anymore), and you could refine its suggestions.