I have 4 greyhound rescue and adoption lists for various activities. 3 of them are very low volume while one has higher volume with about 380 people. The busier list consists of new greyhound owners asking questions about their dogs while the more seasoned veterans answer them. One list consists of volunteers only with about 100+ people which handles emergency transportation and foster homes for greyhounds, events and volunteer opportunities. The other two have 20 to 30, I think. One is for adoption reps only talking about specific greyhound issues and one is for our major fundraiser.
For personal enjoyment purposes, I have one fan list with 395 people that can be pretty busy and two that have practically no volume most of the time. These are Beatles related lists.
Hopefully, I'll see my lists again. I've already set up a back up for my volunteer list on another provider. That one is absolutely essential.