Short bio: Computer Scientist, FOSS supporter (read more)
Tux Machines (TM)-specific
PUD is a Chinese distro based on Ubuntu 7.04 (Feisty) and the 2.6.20 kernel. They've patched in several filesystems and through using SquashFS for the loader filesystem, the ISO is a mere 193megs.
My initial reaction to loading was "damn this is fast" — not just on the desktop but also the much older laptop. BIOS to desktop in 1m23s. Some LiveCDs take that long just to display the opening menu! Most of this is down to how much they've stripped out of Ubuntu (namely Gnome) and have replaced it with the really quite excellent XFCE.
As I've already said, PUD is based on Ubuntu — a Gnome based OS... Why didn't they go with Xubuntu?