http://www.advnut.com/bars1.htm
Atkins bars are $22/box.
I've been very happy with Advantage Nutrition service and prices over the years. I like the EAS Carb Control bars that I get at BJ's Wholesale (like Costco or Sam's), but I think they're phasing those out for their more expensive Myoplex Brand. Carb Solutions bars make me gag. I'm guessing they use too much glycerine and collagen for my taste. Also, Carb Solutions uses partially hydrogenated fat and poor proteins like collagen. EAS bars have a much better nutritional profile.
I've done low-carb /ketogenic diets on and off over the years, but not for radical weight loss like some here are reporting. I use it for getting cut, and have been doing it for short stints since 1991. What I do differs a bit and has been called "The Pork Chop Diet" and "Body Opus". In any case, I eat low-cal, low carb during the week, and then eat high-cal, high-carb on the weekend. Combined with weightlifting, I'm able to lose lots of fat and gain a far amount of muscle in a short period of time. Basically, the high-carb weekend causes the muscles to supercompensate by filling with fluid and carbs, which is what helps with the muscles growth. If I'm really more concerned with bulking up, I'll still go low-carb during the week, but eat high-cal.
In either case, I've had blood work done before, during and after these programs (mainly because my family thought I was crazy), and every single time, my blood lipids (cholesterol, triglycerides) were better during the high-fat, low-carb programs, even when I was eating 30x the recommended amount of cholesterol -- I was eating a dozen eggs, two pounds of meat, 1/2-pound of cheese, and the occasional pint of heavy cream every day. Last time, my overall cholesterol went from 180 down to 150, and my HDLs (the "good" cholesterol), went from 40 up to 50, putting my HDL:LDL ratio (much more important than total cholesterol) in the 99th percentile for good health. My family still thought I was nuts until low carb diets starting getting popular on Oprah and in People Magazine. Go figure. Celebrity over science.
In that short window of time (a weekend), the body will not use the extra carbs to replenish fat stores. In fact, short-term periods of high-and-low calories favors muscle over fat, while long-term favors fat over muscle. That's why yo-yo dieters get fatter over time, but short-term swings (probably 2 weeks or less) produce stronger, leaner bodies. Possible explanation -- during short-term low-cal, the body tries to maintain muscle in hopes that extra work will get some food. If that doesn't work, the body will focus on efficiency instead of performance, cannibalizing muscle (which eats calories even just sitting there) and preserving long-term fat stores. Short periods of high-cal after such low-cal phases, the body will favor muscle, perhaps in "hopes" that restored muscles will help take advantage of this boon of food. Longer term high-cal, and the body will not build muscle (what you have is obviously enough) and will start building up fat for the next famine. You know, the whole hunter-gatherer survival cycle.
Plus, psychologically, it's nice to have a break from the hunger and food restrictions.
Another diet that sort of works on this principle is the Carb Addict's diet. It really works. Just eat lean protein (no carbs, low fat) during the day -- say two chicken breasts. Then for dinner, you have one hour to eat anything you want. Seriously. No food other than that. You won't gain weight, and you'll likely lose it at 1/2 to 1 pound per week until you stabilize at a fairly lean set point. Obviously, if you really pig out, you probably won't lose weight, but you likely won't get fat either. This diet works well if you have a family or like to sit down for dinner with people to socialize. Psychologically, it's one of the easiest and requires little planning.