I know these are all innocent enough. You guys are just looking to generate business... that is expected. We just want to coordinate and work together.
Certainly not a "cartel" but in a friendly spirit of cooperation.

The 2 for a six month committment means 2 in six months. If that was confusing I am sorry. Perhaps we could word that to be clearer. If you think about it... we have approximately 20 sponsors, if each could do 2 per month that could potentially put 80 sales per month into the discussions. Not only would this choke off the board, but it would dilute the value of the sales (afterall, our members can only print money sooooo fast.

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My personal feeling is that the sales should be "special", something that represents an enormous opportunity (and for the most part they have been GREAT deals), and have wide appeal to the membership. In some way these sales become a benefit to our members. I think if we run too many we risk killing the golden goose.
What I would propose as an alternative is coming up with new products. Here are a few ideas:
1) The box at the top of the screen where we are promoting OLF memberships could be occassionally used to showcase new tools. I see this linking out to a separate page that is structured as a "review" and the page could also include links to the company's web site where a member could "learn more" or "purchase" the product. I think we could comfortably run one of those per month -- maybe for a week.
2) Auctions. By donating something to the OLF this in effect gives you the opportunity to run an in-thread sale. If you elect to, you may sell the same item to the entire membership for the auction's closing price. That is a way to come in the back door on extra in-thread sales.
3) Lance and I have been talking about starting an email newsletter for over a year. This is another opportunity. If you run a sale in there it will get in front of ALL of our members -- not just those who are fequent visitors. And, this could also benefit the OLF. If people know that "secret" sales sometimes appear in the newsletter that will be an added incentive for them to take a few minutes to open the mail and read it -- even when they are REALLY busy.
To address your idea of an extra forum to run sales. I think this can cause the same dilution that I mentioned above, plus, I think as soon as we have our auction area up and running you will be able to continously run "sales" for any product you like. We are hoping to make this the "real" luthier's auction site. Ebay is so full of junk that it is hard to pick the peas from the corn.
I think a more professional auction format will allow you to command a little better price for your products and constantly troll for new customers.
Great ideas though... keep them coming.