Renting space elsewhere or leaving them with a friend is your best bet. Unfortunate things happen all the time and although chances are slim for home robberies or break-ins, all it takes is that one time for all of your computers to be swiped.
If you choose not to rent at a storage facility, which I believe most have a one month rent minimum with deposit, then purchase a few electrical timers at your nearest hardware store.
Place a lamp or two near front windows and plug them into the timer, and set it for whenever it gets dark. It'll appear that someone is home in the evening. And in the meantime put your valuable systems in the closet. That way, should the unfortunate still manage to take place, your systems will be hidden from view.
One thing I learned though while living near some of the lower class neighborhoods of N. California is that if someone does choose your house, they will most likely search everywhere. Hiding things will only slow them down very little. And they go for houses that look like easy break-ins. Keeping lights on timers should cause them to think twice, and they'll end up moving on to the next easy house.
