Apache Bandwidth Limiting?

IOOOOOI asks: "I work at a high traffic web hosting company and we're trying to find a simple effective way to limit bandwidth hogs, some of whom we've clocked pulling over 4Gb/hr off our servers. We've tried mod_throttle and have looked into QoS/fair queuing as well as a couple of custom solutions in-house. None of these quite did the trick. Has anyone found an effective way to do this, one that can handle individual connection streams?"