Slackware is truly good in terms of speed and efficiency, its quite a great distro. Archlinux is also worth trying out, it is as fast as slackware and has great package management
btw,
as ujjwal said, u guys should try Archlinux. its optimized for i686 machines and has a very powerful and easy to use package management system.
the installation might not look easy if youre a n00b.. but its worth trying.
I am using gentoo, so i can say i have a tailormade distro. Gentoo 2005.1 will be released shortly, if you have the bandwidth try it. Gentoo forums are amazing, like a linux encyclopaedia!