After beginning my clerk course, I have been in the hospital for long time a day. I couldn't take my notebook because of its weight and the posibility of being stolen. Some of my classmates bought USB flash drives. I remembered Portable Firefox and thought maybe it is a good solution for me.
For several days trying, it's convenient. I had many good extensions installed and made the library’s computer just like what I am accustomed to. But there is a new problem. I found the startup is very slow. I always had to wait more than 2 minutes before I started using it. I don't know why. There is no discussion on the forum. I thought it may because the low speed of the SD card or the USB drive. The speed test (by HD Tune) shows the average is 3.5 MB/s. But strangely, Portable OOo and Portable Gaim work well.
Before I find the solution, I can copy the whole directory of PFF to the hard disc before using, but it's a little inconvenient. >_<