We obviously have general abbreviations like FYI, IMO, ROTFLMAO, etc. Many databases on the net already cover these, apart of the AcronymFinder.com
as Gariver mentioned, I also use UrbanDictionary.com
However the Head-Fi's hi-fi special abbreviations such as KGSS, DAP, PPA, DBT, etc should be listed somewhere (or added to FAQ?). Go on Enzoferrari650, it's a good idea.