I just wonder why people still looking for flash drive when they can use this? http://www.supertechstore.com/ulezbatousbh.html
The cost/size and purpose really, depends on what you need it for. Flash drives are looked upon as temporary storage and transportation between PC's. Because there is no mechanical parts in a flash drive, then shock hazards are reduced compared with the mechanics of a hard drive. Hard drives are more for a permanent solution. Preferance at the end of the end....................
baabaa mentioned size. I can put a USB flash drive on my keychain, perfect for carrying just a small document to work and back or similar uses.
ive got both a 1gb flash drive and one of those HDD enclosures, and lets just say you wouldnt be able to carry the HDD enclousure all day v easily!