Like Howard, Molly & Kiomi, I'm currently on the first page and just got a spam message the other day. I guess that is the price of "fame." I just wish these spammers could be more creative in what they write.
Couldn't they ask me to train them in QuickBooks or properly set up their spammer business financial records in the software, smile?
As for the basic membership, being limited to three messages a day isn't that much. That comes to nearly 1,095 in a year and gives a free member an incentive to be active each day or avoid the hassle by coughing up $10 tax deductable bucks a month (you deduct it under dues and subscriptions).
When you think about it, most of us do list a web site or a phone number so you can make personal contact outside of the site and use your three e-mails for people who don't.
However, if you are going to be a basic member which is your right, I personally think that if you are limited to three messages, you should focus on compliments or add to networks rather than messages per se.
The reason is that for compliments about another member's services, you help them in that some folks need to see some endorsements before they will do business with someone and you can reference back how person "A" helped your business (describe your business) which is a form of guerrilla marketing for yourself.
In the case of networks, you get to plant two crops in one row by being able to send a message and ask someone to join your network. Sometimes, I like to see who is in which member's profile.