I found this site that seems quite interesting ( www.project-world.co.cc ) but wanted to know if i build any of the projects on this site will they really work?

has anyone built any of them before? are they any good?

 

There are hundreds of sites like that on the web. Instead of asking about the whole site, ask about a project you are thinking of trying. You may get similar or better ideas, or find out there are potential problems. After a while you can form your own opinions.