Haven't tried any of KWORLD's stuff, but KWORLD's PCI HDTV card gets fairly iffy reviews on Newegg (3 stars after 36 reviews).
VBOX and DVICO also have USB devices for HDTV that should be considered as well, if that is what you are after.
VBOX and DVICO also have USB devices for HDTV that should be considered as well, if that is what you are after.