I want to utilize a batch of cheap webcams as standalone surveillance cameras?

These are usb cameras, made by Hercules for Ubisoft or some such (packaged for the Wii). I opened one up, there are maybe 3 ics and a bunch of other (passive) components mostly. Obviously this can be done readily with a single board computer with usb ports and an sd card slot. Can anyone make any recommendation?

Would also like to alter the firmware in my Nikon L105 camera to make it record longer then 30 minutes of video. Need help. Would I be endangering the hardware by doing this? IOW would the extra heat be detrimental? I imagine a fan installed in a judicious fashion would alleviate that.

Surveillance implies keeping track of things in real time when needed, not just sitting out there recording stuff to be collected off the SD card if something is believed to have happened (like the camera being stolen) So having several cameras connected to a microcontroller board (not too many, USB has limited distance) still requires Wi-Fi or cable connection to a central viewing station. And have you looked at the quality of "cheap webcams" in low light levels outdoors or in hallway type lighting conditions? The quality of the image is hardly likely to make the police happy in identifying perps.