rtparty
Raise The Reef!
Yes, that'd be considered word of mouth advertising and it's often argued it's the strongest form of advertising there is. You don't see folks running around with tunze shirts or holding pumps in their hands though. They have pricing on their webpage because they sell direct. It's still.. IMHO not the DEFINITION of advertising.
But you do see people promote their stuff on here all the time, don't you? You go to another hobbyists' house and they tell you they have Tunze. People take pictures of their setup and you can see the distinct Tunze styled pumps.
That is all advertisement, IMO. Of course people aren't running around with Tunze shirts on or holding their pumps. It is a different type of advertisement.