Quote “I don’t know what spawned it, but when Cuil attempts to index a site, it does so by completely hammering it with traffic,” the tipster wrote. “So much, that it completely brings the site down. We’re 24 hours into this “index” of the site, and I’ve had to restrict traffic to the site down to 2 packets per second, while discarding the rest, or otherwise it makes the site unusable.”

The Admin Zone forums are abuzz over Cuil’s overzealous method for indexing. Countless posters on the site have said that their websites have been brought down because of the Twiceler robot and one user said it “leeched enormous amounts of bandwidth — nearly 2GB this month until it was blocked. It visited nearly 70,000 times!”

Website owners are also saying that the way Cuil indexes sites isn’t scientific in any way and is actually quite “amateurish.” According to those who experienced the Twiceler onslaught, the bot seems to “randomly hit a site and continue to guess and generate pseudo-random URLs in an attempt to find pages that aren’t accessible by links. And by doing this, they completely bring a site down to where it’s not functional.”
Quoted from http://www.techcrunch.com/2008/09/01/is-cuil-killing-websites/

[...] few months ago one search engine called cuil was launched by former Google employees but after getting huge popularity it was a fail. Cuil even fail to crawl TheChetan.com even after 5 [...]

My website is not indexed anywhere because it is in construction and it is already crawled ! I imagine they have ways to learn which sites to crawl for instance if you install weblogexpert, maybe this program sends your domain adress to them.