So after many years of faithful service my APC ES 750 started chirping tonight. A look under the desk showed a blinking red light. Turning the unit off and on caused the chirp to become an annoying whine. Even unplugging the unit didn't turn off this sound. Removing the battery was the only way. If I understand correctly, the red light blinking is telling me that the battery needs to be replaced. Ok, I have no idea where I would get a battery for such an old UPS. I use the UPS to power my iMac, rMBP, Time Capsule, Cable Modem, Scanner, etc. so it's job is pretty significant. I think I have three options: 1. Plug everything directly into the wall. This kind of sucks because I now have wires all over the place across three outlets in my room. I also have no battery backup in case of a power outage (happens a couple times a year). 2. Replace the battery. Maybe I can find someone to sell me a new battery but wouldn't it cost as much as a new UPS? How do I even know the battery is the only problem? 3. Get a new UPS. Seems the most straight forward and would get me back to where I was. But I don't know which UPS is appropriate for this equipment. Does it matter? What would you do? Or what are you currently doing with your equipment?