I saw this posted at RetroCollect and thought it would be of interest.  It appears a mod is being created for the Sega Dreamcast for HDMI output by electronash. Below you can see a video of this adapter in action.  Using a custom built FPGA and HDMI Transmitter board, this add-on to the Dreamcast sits beneath the console's disc drive, providing a new port on the reverse of the system. Taking a direct feed from the console's video and audio output, a crisp 640x480 signal is sent outwards in a format compatible with just about any HDTV.

The cool thing is that this adapter may become available for other consoles or maybe even for handhelds.  There are no details regarding release date or pricing but you can follow development at electronash's YouTube Channel.

http://www.youtube.com/watch?feature=player_embedded&v=cNuqMp6eemI [/align:1rb9kk4g]