This is exactly what I did as a school project, except I used Phoenix (as it was called then), and the point of my project was to keep the profile on the USB drive for privacy and security concerns. Actually, because of Mozilla's/Phoenix' excellent profile system it wasn't that hard ;-). A word of advice, if you do something like this disable the cache since flash memory has limited number of rewrites around a million and probably most computers that the USB stick will be used on will have fast internet so cache isn't needed. If some want my batch scripts, I can send them but they are very lame, since I had on prior experience, and it was something that I came up with my brain, so it's really primitive.

I'm still trying to figure out how to specify that the Mozilla on the USB should look for a profile on the USB. When I move this thing from PC to PC, it keeps changing drive letters on me. This makes me frowny.

I might actually consider this. It would be nice if Mozilla could allow for relative paths instead of absolute paths. I wonder if there's a reason why the coders went the absolute path?

Currently, my USBs are all on the back of my computer, so it would be a hassle anyway. But if I could make my installation/profile completely portable, I would love that.

I changed the location of my profile. Had one problem though. The profile manager can create new profiles and all, but it's difficult to get it to look at an existing one in a new place. I think I had to hack a .dat file to get it to work.

Unless I'm missing something easy, that makes carrying your profile around a bit harder since those machines don't necessarily know to look elsewhere for your profile.

Zarggg:

Get a USB extension cable and loop it around to your desk or something. I'm lucky in that my monitor base has a hub.

I can use http://www.alain.knaff.lu/howto/MozillaCustomization/ to produce custom registry.dat files pointing to right drive and directory.

I actually produced 7 different registry.dat files (generated using website in aforementioned post), for 7 most likely drive letters (E-J). Fisrt a batch script finds out the letter of the USB drive (this is done by placing a uniquely named file on the USB drive and then using IF EXIST in the batch script to find that unquely named file) and then copies apporriate registry.dat file to %APPDATA%/Phoenix. Optionally any existing registry.dat file in %APPDATA% directory can be backed up and later restored at the end of a session in case the computer already had Phoenix(Mozilla) installed. I bet there's a much better solution, but that's all I could come up with.

Excellent! thanks for that info. I hadn't come across anything like it.

Incidentally, is there some reason why the profile manager doesn't offer a way to select an existing profile in another loction in it's UI? Hacking registry.dat doesn't seem like the most user-friendly way to do something that seems many users would have to do... what's the rationale behind this?

FWIW, I was actually trying to defeat the local+roaming profile that kept getting out of sync as I logged into multiple machines. I have one profile on my server drive, but in a place NOT under the normal windows profile, so it doesn't get copied back and forth, just used directly.