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Hi David, OK first MPEG is not so much a specific standard but a set of guidelines regarding compressed video. Also, MPEG was originally designed to be a "hardware" codec, meaning that a chip is required to both encode and decode the video stream. However, there are some software MPEG codecs starting to emerge (most noteable by XING software). The software solutions are VERY slow to encode, even with a fast machine but is relatively cost effective. XING sells it's software package for about $1000 U.S.. Personally, I use the Optibase MPEG encoding system to encode MPEG video streams because I can vary the data rates to match the device being used to playback the video. For instance, CD-I is a single speed player so I use 1.375 megabits per second data rate and still get 30fps and full screen NTSC video. The RealMagic card can handle up to about 200mbs and plays back video on the VGA screen using the VESA feature connector on your existing VGA card. RealMagic essentially overlays the NTSC video on top of your VGA signal. MPEG really starts looking great when you hit the 400mbs and above rates. Most people cannot tell that the video is compressed unless they are told what to look for and can see the original uncompressed video to compare with. By the way, just so you know, I spent about $40,000 U.S. to build my MPEG encoding system, so it is not cheap. The Matrox Marvel will not encode MPEG but will DECODE MPEG, and does a really nice job of VGA playback. Unlike the RealMagic, the Marvel IS your VGA card so you don't have to screw with the feature connector nightmares. My only beef with the Marvel is that although they say that it can capture AVI (Video for Windows) files, it does not work correctly as the video will not sync with the audio. My guess is that you are going to see a boatload of MPEG decoder cards in the near future, with vastly reduced prices. Sigma Designs just announced a MPEG encoding system to sell for about 4k u.s. coming REAL SOON NOW. Hope this helps, good luck Dean