Single username/password for any platform?

[Blaster]

Is it possible to give someone a single username & password that the 
person can use to login via WPA2-Enterprise from any type of device?  
(Android, iOS, Mac, Windows, Linux, etc?)

I would prefer to not have to distribute certs either, and it's OK if 
the user has to accept a self-signed cert on first connect for each device.

I've been googling this and can't seem to find any discussion that has a 
single cookbook cross-platform example, so I'm thinking it might not be?

For example, my Android device just asks for an EAP password, and not a 
username/password like Windows does.

Thanks...