I used to distroswap all the time - RedHat, SUSE, Debian, Lunar, JAMD, PCLinuxOS, Lindows, Slack, Mandrake, Gentoo, Slackintosh...
However, asides from the occasional change on my iBook - from Yellow Dog to Sarge to Ubuntu to Sarge to Sid to Yellow Dog to Mandrakelinux PPC - I am now a commited Mandrakeuser
It's star stuff...