I've accomplished encrypted channel live streaming using free software.
1) Capture screen at 30 FPS with SCFHDSF,
2) Mux audio and screen cap in Adobe live encoder which also real-time encodes it to x264,
3) output the stream to Adobe Streaming Media server developer edition hosted on the HTPC,
4) connect to the stream anywhere using JWPlayer,
5) use VNC or remote keyboard to swap channels
I stream at 480p and 1.2 mbit, (~50-70% processor usage on an i3-2100), so it's not perfect, but still looks pretty decent. Packet drops/and the ups and downs of home broadband isn't an issue because RTMP protocol has some buffering built in. You also need an active HDMI splitter (about $30) to do the HDCP handshake and to sit between your TV and HTPC so your TV doesn't need to be on the whole time.