PC with multiple video and audio output channels

My wife is a video artist and I want to build for her a PC with three separate video and audio output channels. We want to connect three monitors (or TV's) to the computer, each playing its own video in full-screen mode and its own audio (using either built-in speakers or separate speakers). We want to be able to play videos in diverse resolutions/formats and have greater control over playback (e.g. make them play in sync), hence the reason for building a PC (as opposed to e.g. three DVD players). Can anyone suggest a good solution for this project? Would I need three sound cards, and two or more video cards (assuming two video output jacks on each card)?


APPROXIMATE PURCHASE DATE: within this month (Nov 2009)

BUDGET RANGE: flexible; less than $1500?

SYSTEM USAGE FROM MOST TO LEAST IMPORTANT: playing multiple videos on multiple monitors in galleries; no plans for anything else (such as gaming)

PARTS NOT REQUIRED: monitor & speakers

PREFERRED WEBSITE(S) FOR PARTS: amazon.com, newegg.com

PARTS PREFERENCES: I like ASUS mobos, nvidia graphics cards, zalman coolers, and antec cases+power supplies, but don't mind other brands.

OVERCLOCKING: No

MONITOR RESOLUTION: 1920x1080

ADDITIONAL COMMENTS: If you can recommend a case, something aesthetically pleasing would be nice. I was thinking of getting a micro atx mobo, but if I need lots of card slots I obviously have to go for regular atx. Must have HDMI or DVI jacks. HDCP compatibility is not a must, but preferable. 5.1 channel sound not a must; stereo should be fine, for now.

Thanks!