if there was one recently, it was in 3.x in powers of faerun
though for a discription of it, go ask your qu estion to ED in his thread
why is being a wizard like being a drow? both are likely to find a dagger in the back from a rival or one looking to further his own goals, fame and power
There are several merchant insignias in Power of Faerun but they're all designed as examples and not noted as being the official insignia of any organization. There isn't even one outside their headquarters in the original Baldur's Gate game - just a generic icon.
When life turns it's back on you...sneak attack for extra damage.