They are in the UK, but my division handles one particular part of the network infrastructure for many customers around the world.
I feel like I can tell you about it, but I have to be coy for the search engines. You would know this well-loved Nat'l Service by their three letter acronym, where the middle letter stands for Health.
In my previous job, I was systematically prevented from working with the bigger names because the founder micromanaged everything. I think the most important company I worked with was Union Pacific Railroad. I helped them with their faxing.