U.S News risk calculator
This is a simple, 7 question risk calculator based on the famous Framingham study. It applies only to individuals aged 30 - 74, and yields your 10-year risk of developing heart disease.

The MCW Risk Calculator
This is a somewhat more detailed version of a risk calculator based on the Framingham study

The Healing Hearts calculator
This one also seems to be based on Framingham, but gives a graphical output, and allows you to compare your risk to a target population

A calculator from Heart Risk Evaluations
A one-page, but still thorough, heart risk calculator.

The Med-Decisions risk calculator
Developed by a medical researcher and author, this calculator not only figures your risk, but also makes recommendations on how to reduce it.