CABLE SPLITTERS - A COMPARISON
Nick (known as jafa) over at Silicon Dust (the makers of the very excellent dual, QAM/OTA tuner) wrote about some testing he did on various cable splitters on the SiliconDust forums. The results can be on their wiki here: CABLE SPLITTER COMPARISON
The winner was the Monster SS4RF4-Way Splitter which you can buy at NewEgg for $24.
It's a great way of getting unencrypted qam into your HTPC without a need for an open slot on your HTPC.