Lincovery is an enterprise social bookmarking tool. This copy of Lincovery covers specially following topics: firewall, mac os x, network, limitter, bandwidth.
Bandwidth throttling in OS X
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.
link: http://www.macosxhints.com/article.php?story=20080119112509736