AB ROLLER - If you don't have space at home for gym equipment, treadmil, weights, etc, there are still some accessories you can have that take not to much space but are very effective workout tools.
One we regularly use in our Qeenax class is the ab roller. This little piece of equipment really targets your upper, middle and lower abs and, the more you will use it, the more you will progress in a suprising way.
Like any type of exercise, you need to do it the right way in order to get the maximum out of each training session and avoid any injuries. This is why I recommend you refer to tutorials on the Web. I copied a tutorial that covers what's most important to keep in mind when using the ab roller.
Don't worry if you don't get very low on the first rolls ! You will progress with regular practise and feel your abs getting stronger. Have fun !!