Buying Advertising- PPC - PPV

There are a lot of companies waiting to take your money providing advertising through Pay-per-Click and Pay-per-View. Now everyone knows Google and Yahoo, but I wanted to list a few others I have dealt with over the years. Maybe they're new to you, or maybe it's time for you to take another look at them.

Here are a few of the ones I use and the ones I avoid with a passion.
I will expand on this list as time goes on (as I have worked with over 100 such companies over the years).

Pay per Click
7Search -- One of the best (and most economical) companies I have dealt with over the years. I have run ads for clients ranging from dog food to SEO to skincare products. Traffic has always converted well.
BidVertisier -- Although this company sends good, targeted traffic, they really take control out of your hands as far as setting a budget and controlling costs. You do not have the option of manually funding your account. You put a credit card on file and it IS charged EVERY day for limit you set per campaign. Can get VERY expensive if you’re trying to test multiple campaigns.
adKnowledge -- 4th Largest Advertiser Marketplace. A relatively new one for me, although they have been around since 2004. I found their control panel to be a little confusing, but once I got campaigns setup I have been very happy with the results.

Pay per View
LeadImpact --A very good, low cost, method of increasing your site visitors. Displays your page as a pop-under (Like a lot of companies out there). Although I tell people to not expect sales from PPV traffic, surprisingly I have made several sales in multiple categories using their service. The only drawback I have found is that they do not send a lot of traffic. I think their network is somewhat limited.
VisitorBooth -- For targeted traffic used for making your counter go up, this is one of the best I have found. Traffic is targeted by category and they can deliver at a quick pace, but they limit your pace to a maximum of 1/8 your traffic purchase per day (Not a bad thing).

AVOID WITH A PASSION
Clicksor-- Part of YesUp’s advertising networks. I have never had any good results with any of their network including Clicksor.com, AdOnion.com and xTargeting.com. Yesup seems to be more into selling private label traffic generation scripts than delivering reliable traffic. Great place to lose money. Your results may vary.
AddOn -- I don't think their network actually sends people. I think they use auto-follow bots. I started sending their traffic to pages that require captcha to continue to the advertised site. On this page I added a couple of links at the bottom with no text to click on. To my surprise, the traffic ended up on the pages I had links to and NO TRAFFIC went thru the captcha to the desired page. You can draw your own conclusions based on this.
AdHere.Marchex -- Too many visitors from the same IP at the same time. Really need to be careful about the matching type used for keywords. Lacking in the customer support department.