I am planning on using a laptop on my commute to work to fool around with computer graphics, including extensive use of Photoshop. I find that the touchpad on a laptop is difficult to use for this purpose; something that I can hold in my hand (such as a regular mouse) is much better because it gives me the necessary fine control. However, a regular mouse is not an option because I won't have a large flat surface to place it on.
Do you have any suggestions as to what might work for me?