Fantastico: To start off, and if you haven't done so, you can install Fantastico over your CPanel based server. Fantastico is an autoinstaller that gives your hosting customers the ability to quickly install dozens of the leading open source software into their web sites.

Urchin Statistics: Move away from the default Webalizer or AwStats that offer primitive reports only. Install Urchin Stats on your server and offer your clients a strong enough reason to stay longer. You can even attract many new clients via showcasing Urchin as one of the features. Urchin provides many advanced reports and uncovers intelligent web marketing information. To cover the cost, you can perhaps offer it only on premium hosting plans.

Miva Merchant: Say goodbye to Agora, Oscommerce or any other opensource shopping cart that you have been promoting for sometime. Miva is a commercial product and though involves licensing, the benefits it offers over these free shopping carts are enough to attract many serious webmasters to your plans. It's a comprehensive ecommerce platform with solid customer support from the company. You won't be at the mercy of online forums to help your clients resolve as issue, should it arise.

VPS Software: By installing a VPS software on your dedicated servers, you can actually offer VPS plans to other webmasters seeking for such solution. However, the cost for licensing VPS is rather high and you'll need to find out if your dedicated server provider offers a way for its clients to integrate their servers with VPS cost effectively.