XenExpress
From Xen
XenExpress was a custom Linux distro that actually uses CentOS as a base. The XenSource folks take CentOS, replace the stock kernel with one with Xen support, strip down the install package set to a fairly barebones level (approximately 190 rpms) and then add in a few custom Xen server components.
The current install .iso image for XenExpress is approximately 671MB and includes everything needed to install the XenExpress on a dedicated server machine (no dual-booting here). There are a few other things on the CD including an installer for the Administrative Console as well as an .iso image containing drivers for virtual Windows machines to boost their performance.
