Distributed Checksum Clearinghouse (DCC) is a system of clients and servers that collect and count checksums related to mail messages. The counts can be used by SMTP servers and mail user agents to detect and reject bulk mail. DCC servers can exchange common checksums. The checksums include values that are "fuzzy", or constant across common variations in bulk messages.
HEYU provides a command line interface to communicate with the CM11A hardware module from X10. The CM11A will send remote control signals over the power lines to remote modules within your house. HEYU can be run from cron to automate lights, sprinklers, etc., or can store macros and timers in the CM11A memory for standalone operation. Auxiliary input is supported from MR26A, W800RF32A, and RFXCOM X10 RF receivers for X10, X10 Security, RFXSensor, RFXMeter, Oregon, and DigiMax RF signals (subject to the capabilities of the receiver). Arbitrary commands and scripts can be launched based on X10 and RF signals and the state of the system. HEYU also supports the CM17A "Firecracker" device for transmission of X10 RF signals.