[joeblubaugh]

You can also run multiple haproxies with identical config. One machine goes down? Your existing proxies still balance load to jobs.

[lucb1e]

But people would need to know which other domains run the other proxies. Might as well manually type in the other domain.

The only way I see to avoid a SPOF is with anycast, which I think involves running your own ISP to be able to arrange your own BGP sessions and announce at multiple locations.