I "use" snakes at work for controlling rodents.
We have (had, really) brown norways at work. For several years it was a problem for me, they would chew wiring in our electric lifts and other equipment and cause problems that were very difficult to find.
For the last 10 years or so I have been on a crusade to keep as many elaphe obsoleta (and other snakes, but mainly the black rats) on or near the property as possible. All snakes are to be dealt with by me, no snake killing. If you don't like it, if it scares you, just walk away and call me. I move the ones with bad timing, the ones that don't leave the warehouse before the people get in. I also move the snakes in bad locations; forklift and truck areas, places where people work. All other snakes are left to do what they do.
I have not used poison or traps outside for several years, which was another goal of mine. In the winter I use poison inside the shop and warehouses for the occasional mouse or rat but it's nothing like the problem it was before.
Other people that have been there for a while have noticed and commented to me on the much smaller rodent population is now. Another plus, when moving snakes a few people have been able to get up-close to and some held snakes with me. A few people have changed their mind about snakes, and a few are now more curious than scared. There have been many positive results.
If anybody is thinking about releasing snakes as ratters/mousers in a place they didn't live previously, please don't. Only release animals that already live in the area, species that you have actually seen there in the wild. I wouldn't rely on a free-roaming non-indigenous snake's instincts to guide it to stay in a basement when it is warm out, it will probably leave then die in the winter. In the other extreme, you don't want to release non-indigenous snakes into an area where they might thrive and replace or crowd native species.