One is a compound interest calculator, which will give you total loan amount, after set amount of time and provide a breakdown of how much of this is made up of interest payments.
The second micro project calculates one number as a percentage of another. Neither of these projects are going to set the world on fire, but may come in handy for some, and have exposed me in a very small way to html, CSS and JS integration.
My most recent project will inform you of your take home salary after tax and other deductions such as pension contributions or a company run stock purchase scheme. Take Home Pay Calculator.