Advanced OS X users know that Darwin comes with ipfw, which can be used to set up a custom firewall. This same service however can be used to also limit bandwidth on specific ports.Example:   sudo ipfw pipe 1 config bw 15KByte/screates a pipe that only allows up to 15KB/s to go through.Then:   sudo ipfw add 1 pipe 1 src-port 80will attach that pipe to the outgoing traffic on port 80, effectively limiting the outgoing traffic of the web server.   sudo ipfw delete 1will remove the pipe from the port.[kirkmc adds: I haven't tested this. Just make sure you remember to turn this off when you no longer need it!]

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