I personally would never want to be saddled with a desktop again. I used to build fancy gaming rigs with side windows/lights/many fans, but now I have a laptop that does all I could want anywhere and I can take it with me. I mainly do development/compiling work on it as well as graphics/photo editing and high end gaming. It has an i7 processor, 16 GB of RAM, 512GB SSD and 1TB spinning drive, nVidia graphics, and a 15.6" full HD touchscreen. I also have 24" monitors at the 3 main locations I use it but I can also use it in any old hotel room as well and most have flat screen TVs I hook up to.
As for the actual topic, it has 3 USB ports, I usually have a Logitech Unifying Receiver for wireless Mouse and Keyboard when traveling and a 4 port USB 3.0 hub plugged into it at home with external HD, gaming keyboard and mouse, and web cam.