I tend to use something like this:
<TYPE> - <TIER> - <UNIQUE ID> - <Replicated>
Examples:
DAS-T3-VOL01 = Direct attached, Tier 3, Vol 1
EQL-T1-VOL01-R = EqualLogic SAN, Tier 1, Vol 1, Replicated
Would be interested to hear what others use as well...