Geographic

This is a geographic method of server naming.

Servers:
USMIDET-DC01

(2 Letter Country Code)(2 Letter State Code)(3 Letter City Code)-(Server Purpose)(Server Number)

File Servers:
CAONWIN-FP01

Database:
CAONTOR-SQL07
UKLON-MYS03 (I suppose you'd need an alternative in cases where the state/province isn't well known or non-existent)

Web:
USCASFC-WEB01

Email:
USFLMIA-EXC03

It's fairly basic, but it gets the point across of the server's location and purpose without a reference.