There are hundred of ways you an store inactive data. The question becomes does this data need to be readily available to users and how quickly it needs to be available. One method around this is to implement an archive solution (file based, e-mail based, sharepoint based, etc.). This solution would then move your data out of production to a lowered tiered "storage" like SATA drives, Tape solution (WORM included), etc. In my environment, we implemented a Tiered storage solution which will move less accessed data from faster drives (Fibre Channel) to slower but bigger drives (SATA). In the long run we will save money this way. In additon we plan to implement Symantec's Evault solution which will archive our file, e-mail, and sharepoint resources of production platforms down to lower storage.