Cisco's IOS (availalbe in v12.4) has a feature called the Embedded Event Manager. Is anyone on Thwack using EEM? If so, what do you use it for?
http://www.cisco.com/en/US/products/ps6815/products_ios_protocol_group_home.html
Very short description from Cisco on what EEM does:
EEM supports over 20 event detectors that are highly integrated with different IOS components to trigger actions in response to network events. Customers business logic can be injected into their operations using EEM Policies. These policies are programmed using either a simple CLI-based interface or using a scripting language called Tool Command Language (Tcl). EEM harnesses the significant intelligence within Cisco devices to enable creative solutions including automated troubleshooting, automatic fault detection and troubleshooting and device configuration automation.