The first shop with lots of servers I ever worked in went with apt
musicians' names, which has stood up well enough that I still use it
when I have the chance. hetfield (multi-core), hendrix (huge cpu),
kravitz (low-end box but running slackware so it rocked just enough
in 1995), monk (minimalist but beatifully evocative), a baby blue sgi
server named sinatra, a purple sgi indigo named prince, that kind of
thing. I still use this on my own machines.
Where I work now there's a decades-long tradition of names of food-
related stuff, like traditional dishes: seviche, feijoada, malbec,
etc. This works because we always have postdocs coming and going
from all over the world, such that nobody here actually knows what
every kind of food the servers are named for might look or taste
like. Sometimes makes for long server names, though. They all get
aliased to more useful public service names, but we still refer to
them by their food names here.
Worst server naming strategy ever: DDC based on a rough assignment
of server roles. e.g.: "this one is being used for a blog written by
patient caregivers so we're calling it '808.899213620425'."