Don't really have a schematic for this small project. I had an MC34161 (datasheet PDF link)
I actually haven't tested whether the chip's built-in hysteresis is enough to prevent oscillation yet (large load on battery -> battery discharges below 10.6V -> battery is disconnected -> battery voltage rebounds ? -> ? above hysteresis threshold -> repeat until something melts/breaks/explodes)
This is obviously something to avoid. It's probably not a issue for me because it doesn't matter for the devices I'll be powering off this battery. (I'd just realize what's going on and power them off) but it's something to keep in mind in case anyone builds something similar based on this chip.
UPDATE: Ok, you probably shouldn't build this unless you use an extremely low RDS-on FET or something. I'll be modifying this to work as an undervoltage detector and to use a bistable relay when I have the time. This'll also have the advantage of solving the hysteresis issue (the relay will just switch off when the undervoltage detector triggers it). If I set up the chip as a dual detector I could use it to switch the relay back on when the voltage rises above say.. 13 volts. I'll either do that, or just add a "reset protection" button if I'm lazy. (I'll probably just do that)