One hot trend on the rise is the use of live linux. Typically live linux allows for a PC user to boot and run a linux operating system from a CD.
In it's most basic form, live linux lets the PC user test drive the operating system to see if they like it before doing a full linux install to a computer's physically attached internal hard drive. Live linux applications can also be used in emergencies when you need to fix or repair a computer that has a virus or file corruption. Some might use it when a computer has encountered complete hard drive failure and they need to get to the internet, check their e-mail etc. One of the best things about live linux is that it leaves no traces behind on the client computer because it runs completely from it's own media and or system memory.
For the most part, the live linux advantages are great. It's portable, able to run on most PC's today, is virtually hack-proof and virus free. However, there is one major fallback to running linux via a CD drive that seperates this from a fully cabable operating system environment that you would wan't to work with and use every day.
Live linux natively contains virtually no read/write support. Once the Live CD is created, you can't really edit it or save even your basic setting changes, favorite bookmarks, e-mail etc back to the same CD. Well, there are some works in progress that allow the use of a CDRW drive for read/write support but writing changes to a CD is typically too slow for the average user to feel comfortable using this live method.
This is where USB flash drive technology comes in. We have now adopted a faster USB standard (2.0) and most newer motherboards being produced today have the ability to boot from a USB Device. With these recent advancements, the merging of live linux and USB Pen drives becomes natural. We can benefit from the increased speed, have read/write capability and even more portability using a live linux pen drive vs. live linux CD.
If you'd like to experiment with live linux on a usb flash drive, you can find a complete list of walkthrough tutorials at Pen Drive Linux https://www.pendrivelinux.com/
Pen Drive Linux explains how install various live linux versions to a pen drive. This allows a person to bring linux and their personal settings with them to quickly boot on a computer that supports USB boot.