If it's for ATSC, you have a few choices
1 - orblive, feature rich (live tv, camera, video file) and not-focused(trying to do too much), ffmpeg based, works with most tuners, windows only
2 - telly, OTA ATSC streaming only, ffmepg based, works with most tuners, windows only. Simple interface. If you simply want to stream OTA ATSC TV, then this might be your choice.
3 - eyetv, mac only, errrr...expensive tuner
4 - wintv extender, for wintv tuner only
5 - slingbox, a lot more expensive.