Two new venture-backed startups go after the stay-at-home market.
Industrious Kid, founded by former execs at Ascend Communications, just got $6M in venture funding to start Imbee, a MySpace-type social networking thing for 8-year-olds (and above). At $40/year I just don't see it taking off, though. Any parent involved enough with their kids' internet use will be involved enough to chaperone them on MySpace for free. Why bother with less?
Club Mom wants to be a social networking site "for moms, by moms".
Again, I'm not sure what the market is. Everybody wants to create a "community", but rather than force people to come to you, I think the future is in aggregation -- let people go wherever they want, and you come to them.