What are some good test to run to benchmark OS's on the same hardware?

Not trying to flame Solaris or anything, but I'm curious because I run several *nix's on my box, and Rawhide always seems to visually/perception of running the fastest, and Solaris(nevada/opensolaris) seems to perform the worst.

So I would like to run some test to find out if my perceptions are all biased :)