Viability of nginx instead of hardware load balancer?

[John Moore]

I'm working on a project where it's critical to minimize the possibility 
of a single point of failure, and where there will be quite high 
traffic. Currently in another version of the system we're using nginx as 
a remote proxy server for Tomcat, but the current plan is to use a 
hardware load balancer in front of a Tomcat cluster (or a cluster of 
nginx+Tomcat instances). I'm wondering, though, given the extraordinary 
performance and reliability of nginx, whether we might be able to omit 
the hardware load-balancer and use instead a couple of dedicated minimal 
nginx servers with failover between them. If anyone has gone down this 
path and has some good ideas and/or useful experience, I'd be keen to 
hear from them.