Do it yourself … “What Resources?” Not exactly something we built ourselves, but thanks to our local Emergency Operations Center (in combination with our local Dispatch / Communications Center who use it for community-level emergency notifications) we have access to what I’d term “team-level” Everbridge mass notifications system.
Using Everbridge we can send a message to all our team members; phone (land line, mobile, work), email, TXT either in priority order (with time delays in between) or all at once … all devices / mechanims - almost instantaneously.