Pointing out interesting finds / 75mm Mexican

I was wondering about posting some interesting links which I often come across and wanted to see about the appropriate way to do it. Often times while perusing Gunbroker or Auctionarms I’ll come across a unique and not often seen collectible cartridge or piece of ordnance and I want to tell people about it if for nothing else than just to point it out as an interesting item, or to get reactions as to how rare or authentic something truly is. Should that type of post go in the buy/sell/trade folder because it is a listed item for sale even though it isn’t mine? I ask this because I come across a couple items a week of this nature and I wouldn’t want to seem like an advertisement for anything or anyone. Or worse, start a trend of people directing others to items for sale through the general section all the time. The interesting item I had most recently noticed was this one: http://www.gunbroker.com/Auction/ViewItem.asp?Item=132740235 I especially like finding odd or rare items which have been listed poorly by the seller with main-title words which are misspelled or which would not direct most searchers to that auction, but which I find coincidentally.