Firefox and Thunderbird, as well as some other applications, have portable versions available that run entirely off of the flash drive. Thus, you can take your favorites, e-mail, and preferences with you, and leave little to no trace on the computer you used. You can download portable Firefox by clicking hee and Thunderbird by clicking here.
As to the surfing 'protection,' it depends what sense it's in. For instance, do they mean leaving no trace of browsing history, cookies, and such on the computer you used, or do they mean the usage of proxies to prevent the sites you are visiting from knowing your identity. Either way, portable Firefox can handle this.
Finally, when it comes to encryption of your data, always a nice thing to have considering the personal information stored on such a small, and easily misplaced, device, there are plenty of free options. Remora USB File Guard is one, and Omziff is another. On top of that there's the Simple File Schredder (to securely erase files, never use the recycle bin), and Portable OpenOffice for mobile productivity software similar to Microsoft Office.
Honestly, with the number of free programs specifically designed for use on flash drives, I see no reason to fork over the extra money for a 'secure' flash drive, or one that comes with free applications pre-installed. Just get a 1GB flash drive for $50 on sale, download a few applications, and learn what it truly means to be portable.
Hope this helps,
John
I've seen a couple of sites offering secure internet ready flash drives of 128MB-G with Fire fox and Thunder bird loaded on and various other things to encrypt email, and surf anonymously so you can use it safely from an internet caf
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