As most of you probably know ESX Server requires supported SCSI disks for running VMFS, the VMware proprietary file system where virtual machines are stored.
This slows down the spread of ESX Server in home testing environments and the upcoming ESX Server 3.0 won’t help much, introducing support for iSCSI and NAS but not for IDE/SATA.
But since more than 1 year there is known trick to workaround the limitation: using some special SATA/SATA2 controllers which use SCSI drivers.
Richard Garsthagen, a VMware employee, published a funny story about how trying to get ESX working with a SATA controller can actually be much more expensive than buying a SCSI subsystem.
By the way he also confirmed that the SATA2 MegaRAID SATA 300-8x controller works great for ESX 2.x and upcoming ESX 3.0 (at least on the actual beta)!