I think our Kips having a bit of a rant
Do have to disagree though, the free route does actually work in some cases.
To give an example, go to google and type in
northampton county court
Round about 4th entry down should be a My Local Services one. Now this is a free listing, and I can tell you it gets thousands of pageviews. So in this case it works. Just in the same way as it does with the likes of FreeIndex and many others.
Using our model, we would upsell to a customer, as the free listing has minimal SEO value, with no weblink back to the customers site. But in this particular case, no one really cares, as 90% of people just want the phone number or address, which is displayed, and the court aren't interested in advertising their web link
But it does show that a free listing is just as capable of generating pageviews, its the chance to convert into sales, via advert wording and web links that suffers.
But when it comes to "list on 100 free directories" I do agree with Kip, and spreading your business over 100's of free web directories, which is normally a page of links from a script driven directoiry will offer you little to no value, and could well cause you problems. Do you want to be associated with dodgy sites displayed on the same page as you!