Liz Gannes over at All Things D is reporting that “people-search” engine Ark has just raised $4.2 million during its recent seed round. Ark is a website that promises to help searchers find old acquaintances and new friends based on search parameters. The site can currently only be joined by requesting an invitation from Ark. A Gmail-type invitation system is being used, though, so anyone who already has an Ark account can invite others. Gannes reported that more than 250,000 people have requested invites already.

Ark is a recent start-up that is part of Y Combinator investment funding. Y Combinator is an interesting investment group, which twice a year gives small amounts of money to start-ups so that they can get their company into shape for an investment pitch. Y Combinator then holds a “demo day” for all of the start-ups to pitch to investors. According to Gannes, Ark’s pitch got the company $2 million in a single day.

Ark bills itself as a search engine for finding people, but it has limited functionality so far. The only people Ark can sort are those whose information is public on a social network. To find those people, users must use search filters such as location, employer, schools, and interests. The site seems tailor-made to be bought by Facebook to enhance their site search.

I should also mention Ark’s strange obsession with penguins. Their site is covered in cute penguins, and their Facebook page includes a photo gallery packed with groan-worthy penguin comics.

What do you think? Are the search engine wars heating up again? Will the search landscape fracture into a series of specialized search engines good at only niche searches? Or are investors jumping onto the bandwagon, hoping for a Facebook payday? Leave your comments below and let me know.