I run my CCTV of 4 cams into a DVR with a 500 gig HD. Stores about 3 weeks continous recording at 640-480 res and 24 frames/sec.
DVR is ethernet compatible with own IP address, connected directly to router and the net, accessible without any PC as long as my internet is up.
Via coax DVR is connected to PC and TV, this allows inhouse viewing from anywhere via wifi and TV....