It doesn't have to be spam to be effective.
E-mail is a very effective way to promote your services.
Keep Email Content Friendly, Relevant and Up-To-Date
Don't sent the same email every day. Most of the time, those emails will get ignored, and may even solicit complaints from the recipient. Make your first email a welcome message, explaining the purpose of the marketing campaign. In subsequent emails, make products specials available only to those "special" customers who receive the emails, making them feel important. Don't offer the same specials in every email.... vary the products, and give them previews of upcoming events, services, or products.
Personalize Every Email
WebDiddy can include the ability to personalize every email. Make the welcome message say "Hello again, Mr. John Smith" rather than "Dear Customer". If your client feels like you are sending them something directly, they likely will respond more frequently. Make every client feel special.
Double Verification Opt-In
Don't send unsolicited e-mails. Opt-in assures the people you're sending to want to hear from you and hence boosts list quality. This is a dramatic departure from the opt-out process most append vendors adhere to, in which they assume anyone who doesn't respond wants to hear from you. When a visitor wants to receive emails from your company, WebDiddy will set up your program as a double-opt-in, which means the visitor must verify they really want to hear from you, by clicking a link in the content of the initial email. Quite often, you'll get people who include their email address, but then regret it. This process will assure that they do not get unwanted emails. Additionally, this saves you from sending emails to addresses that don't necessarily belong to the person filling out the opt-in form. By verifying the opt-in, you are assured that the email address entered doesn't belong to someone unknown to, or not liked by, the visitor.
Easy Opt-Out
Don't make your clients feel like they are trapped into getting these emails. Every email sent out in a marketing program should include a link to allow the recipient to opt-out at any point, without any risk of receiving further unwanted emails.
Frequent "Old Address" Purging
WebDiddy can setup an automated function that will send out periodic emails, asking for your clients to verify they still wish to receive the emails. If they fail to respond to the email, that email address can be considered expired, and the email address would then be purged from the database, saving on valuable bandwidth which would've been used sending emails to unused addresses.
When used responsibly, this can be a very effective and efficient way to get the word out.