I create and sell business software for writing invoices and managing customers. It is also available for rent and I use the following stack for my own cloud:

Debian, KVM, Apache, MySQL (with Percona for clustering), GlusterFS, rSync, HAProxy, PHP, jQuery

I actually own 3 servers :) I know, it's super boring, but this stack has only failed me once in about five years.

Yes, in my opinion this stack has helped me a lot in earning a living with my company because it just works and saves me time to do other things that earn money.