You must use mHSRP to do "load-balancing"
If you need help about the config don't hesitate to ask.
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Most implementations that I have seen in datacenter and enterprise networks are as follows.
Router-A will have 10 HSRP Standby Groups as the Active Router, and Router-B will have 10 HSRP Standby Groups as the Active Router. Obviously each others router will be the Standby.
Now, 10 is just a number I picked.
I'll let Cadet throw down the config
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As Alain and John have described, you can load balance, for the same subnet, if mHSRP is supported. For different subnets, you can alternate which router hosts the active gateway, i.e. mHSRP isn't required. The former also requires you somehow have hosts use the different mHSRP IPs, which is a pain. If you're equipment supports GLBP, you might find that a "better" solution.