SNMP Simulator is a software that would act like a multitude of real physical devices from SNMP Manager's point of view. Simulator builds and uses a database of physical devices' SNMP footprints to respond like their real counterparts do.
Project moved to GitHub: https://github.com/etingof/snmpsim
An implementation of the Open Groups' ARM (Application Response Measurement) 4.0 Java interfaces. OpenArm can be configured to send ARM transaction data to a log, to a messaging queue, a datastore, a JMX notification or to an SNMPtrap.