I had a similar issue with my DSL connection at home. Using SSH was really painful, when someone was downloading...

A lot of people got down to the nitty gritty technical details, but as I understand you want something simple that just works. Well, I use a Linux Firewall distro to do the routing in combination with a small script to configure the QoS.

Try Clarkconnect in combination with Wondershaper. Wondershaper uses some basic input parameter to configure the kernel to traffic prioritization. I found it very easy to define my available bandwidth, what services require a higher or lower priority.

Every product that I've ever bought from SonicBlue has been malformed and returned to sender.

The technology sounds cool, but I'll probably wait until it's available from another vendor.