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I spent $70 on one of those slider titanium Sandisk ones they used to make.. it's only half a gig but I've rarely had any need for anything larger than that.

Thing's been throughout he wash, in the dryer, dropped in the mud, run over.. still works great.

Mostly I've used it for dragging valuable files to work, when I worked away from home
 
other than having access to (limited) storage anytime, thumbs are great to always have your software profiles with you. keeps you efficient on any machine you might work on.
 
Use them all the time to leave job files with printers or transfer files around. Small and convenient. Better than cd and reusable. Own several.
 
I keep a nice 16GB aluminum one on my keychain. It have whatever OS X is current, Arch, and 6GB worth of misc. admin type stuff. I also use DVD's some so I'm obviously a bit old school.
 
I have collected several of them from over the years. Now I mostly use just a couple for making OS X installers. I've got 10.7.5 and 10.8.5 on a 16GB one and Mavericks on an 8GB one.
 
Picked up a USB 3.0 16gb one at Microcenter for 10.99

Use it for random things. Mostly to watch downloaded shows on my TV via the PS3
 
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