The CamStudio codec comes with its own Lossless Codec that does produce crystal clear video and audio results with a much smaller filesize compared to some of the other more popular codecs, like Microsoft Video 1.
The Dolby Digital AC-3 decoder and decompressor for the Windows ACM. You first need to install this codec and you can then only convert or decompress the AC3 audio file directly to WAV or to MP3 using. This codec also works with other players such as AviSynth, TMPGEnc, allowing you to use AC3 encoded AVI files.
The Panasonic MPEG4 decoder is a plug-in which allows you to playback any of videos which have been recorded in extra fine mode with certain Panasonic D-Snap digital camcorders. It will not play none standard files.