Don't like the fact that you only have 2 internal USB ports?
Then you should consider investing in a 4-port/7-port usb hub.
Powered or Non Powered.

What is a USB Hub?
A USB hub provides additional ports that you can use to connect external devices to your computer or console. While higher-end computers may give the user a generous number of ports, budget-priced desktop systems and many laptops provide only a single USB connection, making a hub very useful. You can choose a powered USB hub or a non-powered hub; both have pros and cons depending on your individual needs

Non-Powered Hubs
All USB ports are powered in some manner. The built-in USB ports on a computer are powered by the computer itself and don't require an external power source. A non-powered USB hub works in the same way, drawing power from the computer. The downside is that the battery life of a laptop can be drastically reduced. These hubs typically allow up to four USB devices to be connected, and each device adds to the power drain on the computer. Non-Powered hubs are recommended for low power consumption devices like mouses or keyboards.

Powered Hubs
A powered USB hub plugs in to an electrical outlet and draws power from that source rather than the computer. Larger devices such as USB powered printers, scanners, and external HDD's. A non-powered hub will work just as well. However, a powered hub is a good choice if you want to connect a number of large USB devices to a laptop computer. There's not enough power for your console to equally sort it out to all those large devices on a non-powered usb hub, Thus, having a powered usb hub is the way to go.

Advantages and Disadvantages
Powered USB hubs will prolong the battery life of a laptop computer by reducing the draw from devices connected to the hub; however, these hubs cost more than non-powered units. For larger devices that have their own power, and for desktop computers, either type of hub will allow suffice. Traveling professionals will find powered USB hubs more convenient for connecting multiple small devices such as digital cameras and flash drives to a laptop.