Which traps are useful when using SNMP

Looking at implementing SNMP management on 200+ NT 4 servers (including some MSTS servers) and 300+ Netware 4.x servers. Has anyone done this and specificaly what traps were used and then found to actually be useful and save support time. I can findplenty of info on how to install and configure SNMP but not how to use it in practice in the real world.

thanks,

Glenn