Not that I hadn't already done plenty of CRUD in SQL in jobs prior, but for 4 years I worked on streaming stock quote servers. All in all the system had 500+ servers deployed in a tiered setup. No data was persisted to disk (save for some config), and no SQL was ever involved. Ticker symbols (CUSIPs) did need to be looked up and those went through our network, but the actual lookups went out to a service, and results were cached.

That's just one example. I'm sure there are many.