Without a doubt, USB flash (thumb) drives have replaced "floppy disks." I remember paying about $75 for my first drive four or five years ago, and it was only 16 MB. Now, Audi will send you a new vehicle brochure on a 32 MB flash drive.
Times have changed, however. Just last week, Buslink just announced a 64-gigabyte flash drive (pictured at right). But this little puppy isn't free: You'll need to plunk down $5,000 to own it.
But, recently, Kanguru announced a 64-gigabyte flash drive of their own for $2,800, close to half the price of the aforementioned drive. At this rate, it certainly doesn't make sense to run out and get one. If you wait a few weeks, another company will likely offer one for $1,000.
You are much better off with the free Audi drive. True, it won't store many audio files, but that is an amazing amount of free storage for most all your text files.