gistfile1.txt

iptables -t mangle -A PREROUTING -j ACCEPT -p tcp -m multiport --dports 80,443 -s ! 192.168.1.134
iptables -t mangle -A PREROUTING -j MARK --set-mark 3 -p tcp -m multiport --dports 80,443
ip rule add fwmark 3 table 2
ip route add default via 192.168.1.139 dev br0 table 2

# 192.168.1.134 is the source I want to redirect, 192.168.1.139 is the proxy, and iptables was run on the router (192.168.1.1). The proxy was listening on port 80.