[scaryclam]

Some segregation is useful. If a key I use for work never touches my personal machine, that's a good thing. If my work laptop gets stolen I don't want to have to cycle my personal key, etc.

I guess the point I'm making is more for making decent keys to create sensible separation points, rather than having one for each machine though. Allowing work vs home vs foo vs bar

[jamiesonbecker]

Right. We usually recommend a single key per client device (laptop, desktop, etc), because that way you can rotate that key if it gets lost/stolen without changing your other devices as well. This way, those private keys stay totally local to the device and never actually need to move, which is much safer. (I work at Userify.)