Normally what I do is go by [deptartment][phone extension]
For example, for a sales deptartment that was 5 computers, with 5 phone extensions from 100-105 I would do:
sales100
sales101
sales102
etc.......
This way it is easy to tell exactly where the computer is, just goto the phone extension. I also try to put the IP addres's within the same format, really helps streamline everything for me, that or I just over do things
Example:
sales100 - 192.168.1.100
sales101 - 192.168.1.101