Home Cctv

My buddy wanted a camera system that he could hook up in his house to monitor it when he is out on business. He wanted to hook up 5 video cameras in the house and then be able to view them on his computer via internet while away. Is this possible? If so how do we do this?

If I have a desktop with monitor connected to internet (ready to run 24hours). I wd like to setup a home CCTV network (DIY) so that the monitor will always display the streaming video…What components should I buy? Is there any special card to be plugged in to the mainboard to accept video signal from multiple cameras? Please advise, thanks!

p/s: I wd give up wireless IP camera since they are too ex!
p/s: The reason I mentioned that the computer is connected to internet is because, it wd be best if the images can be viewed from internet!

Please advise me the suitable range of software and hardware to achieve this! Thanks!
Oops. Most importantly, hard disk recording!!

P/s: Web monitoring can be excluded. Most importantly is a good capture software..and good hardware combinations! thanks!