A lot of people want this, and while I don't really care, there are some instances where I have to use DB chat (i get trollbanned like every day) and with the plethora of people and the terrible framerate, I bring you this.
If anyone mentions me in chat ever, I don't see it and bad things happen. My solution to this is, if they put an '@' sign before your username in chat, it plays a sound like a bell or something and it highlights the message. For example...
>hey whatson u r lame i hate you you are a terrible user
Yeah..? Well i'll never get your message because I am on another tab, try bothering some other bad user.
>@whatson i hate your suggestion scraf told me to say that
This happens except I will hear a ding that tells me someone mentioned me in chat and the message is highlighted so I can find it easily.
...and I just realized most of the meta community that has the sense to vote uses the DB showdown server chat and not the site chat.