How about Puppy?
http://www.pendrivelinux.com/puppy-linux-on-usb/
I'm looking for a flavor of Linux to install on my flash drive as my general "computer-2-go", I've tried a few so far, my favorite being Ubuntu as I'm still new to Linux and this seems to be easy to learn on. But basically I'm looking to see what else that fits under these qualifications so I can try them out... I love messing around with different distros.
1. Able to run on a computer as low as a 500Mhz CPU and 128MB RAM
(It'll be rare I'll be on such a slow computer)
2. Able to run off a flash drive in no more then 4GB space
Yeah not many requirements really. I just want to see everything you guys suggest and try some (if not all) of them out. I'm using Ubuntu on my flash drive now, so far I like it, just it can boot a lil slow. I have a ton of computers I use and having a flash drive with my own "computer" on it just makes things so much easier. Not to mention it's a fun thing to mess with/show off. Lol.

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