Can anyone recommend low-cost traffic shaping/ip accounting DIY solutions?

My boss is asking me to implement some type of network traffic-shaping for
our webhosting business.

I have been looking into few commercial solutions such as Packeteer's
PacketShaper and Cisco's 3800 Integrated Service Router. Needless to say,
they are way too expensive for us to deploy. I need something that costs
around $1000 and rack-mountable (1U / 2U). Thank in advance!