How can I automatically disconnect a coffee maker and space heater without tripping the building's 20A circuit breaker?
Put your computers on a UPS, even a small one. Just protecting yourself from short power outages will save you a bunch of downtime. Even if you resolve your overload issue, this is still worth it.

Most computer users today can get by with a laptop that's under $500, giving you built-in battery backup &amp; portability in a compact, low-power package. Plug it in to your keyboard, mouse, and monitor the same as your desktop today, so your work experience doesn't change.

The power strip you linked to (http://www.cyberpowersystems.com/products/surge-protectors/home-surge/6050S.html?selectedTabId=specifications&amp;imageI=#tab-box) doesn't appear to have a breaker. I think that whoever wrote that was just confused about what it means to be rated for 15A. 

If your coffee maker and space heater are in the same location, you could plug them into mutually exclusive switched outlets. You'll need:


A steel square box, and an appropriate face plate
A regular duplex receptacle. 15A or 20A can work
a 3-way switch
cable
plug (15A or 20A, to match the recep)
fittings


Snap off the tab on the hot side of the recep, then run short leads from those 2 screws to the 3-way switch. This will let the switch choose one socket or the other. Plug in the heater on one and the coffee maker on the other. Now it's easy to make sure only one is in use at a time.

(Later I will add some pictures and other details. If anyone has pointers to the correct fittings and cable, please comment.)