1)   MoneyToys - Discounted Cash Flows applet 2.1.1
MoneyToys Discounted Cash Flows Calculator for web sites lets your visitors easily calculate the net present value of a series of cash flows without leaving your site. Installed and configured with only a few lines of HTML.

 2)   Mortgage Prelude 2.3.1
This FREE mortgage calculator computes such items as your monthly payment, amortization schedules, interest, etc; but it is so much more. You can actually find out how much of a mortgage you are qualified to get!