Steve,

Any thoughts on cost effective HA plans when Vitualisation and SANs are in the mix?

What recommendations would you make if the windows server is virtual and hence also the SQLserver?  Further, if the drive holding the SQL data is on a replicated SAN would it be better to let the SAN software take care of the replication at a block level to a DR site (tempdb excluded).  A Read/write production and a Read only warm standby would aleviate the log shipping problems mentioned above. 

The HA plan you choose depends on the disruption you are expecting:  Hardware Failure (NIC, Disk), OS repair/updates, Data corruption (by User / other) , network  etc.