SADA is the Southern Alliance Drinking Association. It's the namesake of the SADA's Brewmasters RC in Perdan. For a long time it was a very large guild. I forget how many members it had. It got destroyed during some guild maintenance bug or other in late '06 when all the guildhouses fell spontaneously fell apart. Various attempts to revive it never really got any traction.
POPLN/OPLPN is the Perdan Oligarch Liquor Pipeline Network. Or something like that. This was even older than SADA. Was popular back in '05, before I joined, and perhaps even before that. I'd heard it mentioned several times, but don't really know any details.
*sigh* ... So few people remember...