My absolute favourite job was also my most challenging.
I was working as a Librarian in an inner-city branch, we actually had a panic-button under the circulation desk.
It was a regular occurring to have to call the police because of the prostitution happening in front of our building, the pimps would watch their girls deal with Johns from inside our Lib.
We had a head-shop right across the street, and a men's half-way house just down the road. I'd have extremely stoned (or even more frightening, tweakers) come in, and ask things like: "Can I buy your urine off of you?" (seriously...)
I did a teen after-school program, and had to dive to catch a 16 year old girls, 6 week old baby from falling off a chair, (she'd put the carseat on a chair, it was too large...)
Thankfully we had a male librarian who would rouse the homeless who would sleep on our lawn all night - and we'd offer free food and coffee during the winter, as much as we could.
Almost worse was the children - we were right near a high-school, and the things I saw/caught them doing was awful, not to mention the little toddlers that would run around crusty faced, dirty and asking for food while their mom's browsed Facebook on our computers.
It was more than a job, it was a real ministry and service to the community. I only had to call the police once, and had to have Hubby pick me up from work, as it was too dangerous to go alone (or with another tiny female co-worker) into the parking lot to get to my car.
I was sad to leave...