the Adaptec ASR 71605 work great and support up to 16 hdds. Press ctrl-A while booting, and you can switch modes from RAID to HBA (IT) or vice versa. no need for flashing.
on ebay, they run from $40 (with no cables) to $100 (with 4 cables) a piece.
These do require a lot of airflow. So unless you're putting these in a server chassis, you'll absolutely want to strap a 40mm fan on the heat sink. You can use zip ties, or m3 bolts into the extra holes on the heatsink.
note: if you already have an lsi card, these use different connectors for the breakout cables (sff-8643).