You've got your usual suspects; EMC, HP, and IBM. All of those vendors have rolled out targeted efforts to gain space in the SMB share. You've also got NetApp, known as a leader in NAS, who supports iSCSI block data and file sharing in the same array.
Many major vendors now support shared block and file storage in the same array. For SMBs it's really important to think about a unified [or multiprotocol] storage deployment in the SAN, because most small businesses need both block and file data. An iSCSI SAN can be a good solution to optimize an iSCSI storage investment and increase utilization, because so many of them now can serve both file and block-based data.
Check out the entire iSCSI SAN FAQ.