If you buy links on cloud sites with your keywords will that increase site rank? will it increase PR?
Cloud Sites are bad links with unrelated links and can be look as link farm for search engines (lot's of links in a single page) read all about Cloud Sites
They are one way links IBL so if a site is not linking OBL then we are ok. We can not control who links to our sites so it can not hurt. Ninja - Do you have an actual example of this happening to you?
You don't have to spend too much money for a world cloud link- some guys sell it for something like a buck and it is a link- it may not have that much value..but a link is a link
Yes, a link does not cost much. In addition, some allows you to sell the links back to them at a higher price