Nakakita ako dati sa ACE Hardware ng electronic or magnetic sensors na kinakabit sa pinto at sa frame ng pinto. It will trigger an alarm if the current passing through the two components is disrupted. I just don't know how effective these are.

You can try Googling home or office security web sites like Home Security Store, kaso nasa US ito.

If the crooks still make it inside your store, you can still give them a hard time by making your equipment harder to carry out. If its feasible, you could bolt down your CPUs to the table or floor, or pass cable locks through them. Yes, these security measures can be defeated with time and determination, but the objective here is to make the crooks take longer in carrying out their work so that hopefully, an alert passerby will have time to call the cops while the thieves are occupied.