We've tested this trick in Flowdock, but it probably works in others.
Most of the current breed of hosted team chat services (Flowdock, HipChat, and so on) allow you to upload custom Emoji files. I say "allow" like that isn't their primary purpose. Anyway, you can abuse this feature to conveniently ping predefined groups of users.
Upload a new emoji including the names of each member of the group you want to ping, prefixed with a handy team name. At Boundless we're all pretty much full-stack, but in practice each person primarily focuses on backend or frontend concerns.
Thus, our team emojis are:
: to pull up the custom emoji list, and you will be able to autocomplete your team name. Everyone mentioned in the alias will get a ping.
Huge hat tip to Adam Fraser for this one.