One law department I consulted to arranges monthly lunches for its members. The lunches are in a conference room, and the department pays for sodas and some dessert. People who attend bring their own lunches.
The department sometimes uses the lunches for very short presentations by a lawyer or paralegal about matters they were working on. This allows others in the department to get a sense of what is going on. Primarily, though, the department’s managers see this small investment as a way to create a more congenial environment, to punch some holes in the silos, and to help people to get to know each other.