One thing I like about my current host, Rackspace.com, is that they provide options for scaling up my site as required, such as load balancing, multiple boxen on an internal low-latency network, and so forth.

I'd like to find someone cheaper than Rackspace and with better options for upgrading hardware. Who else provides the kinds of advanced network configuration options that they do?

Most managed server providers can do this.
They may not have info on their sites about it though. You really cannot have preset pricing on many custom situations.

...so just as you need a custom config, you also need a custom quote :-)

Contact the providers you are interested in, and explain to them what you are looking for exactly, and they'll assist you...

Warm Regards,
Sean R.
BurstNET