Hey Rich,
If you're "future proofing" a cable run to the PJ location, I'd recommend you run some conduit through your wall/ceiling so the cable can simply be pulled through at a later date. Maybe a couple conduits, each being at least 1.5". One could be for HDMI and the other could carry three runs of RG-6 for RGB (component).
I agree with the statement that for 1080p you'll end up needing an HDMI cable.
A run of component cables to your PJ would be nice as you never know what the future holds regarding video sources. Personally, I'd run an individual conduit for each type of cable your PJ will accept. If yours has S-video and composite inputs, I'd run a seperate conduit for each of these. You never know, you might end up with some device that has on screen menus that uses a composite (single yellow RCA) cable to the display devise.
Regarding the actual cable;
- Oppodigital.com sells a 25' HDMI for $36. I bought one of these and it's a big heavy fatty of a cable. Very nice indeed. (but slightly short for your situation)
- Blue Jeans has many options with a wide range in price (but all are resonable) here:
http://www.bluejeanscable.com/store/hdmi-cables/index.htm- Monoprice.com has a "truckload" of HDMI cable options:
http://www.monoprice.com/products/subdepartment.asp?c_id=102&cp_id=10243Bob
EDIT: Oops, Bryan beat me to it.

I wasn't typing fast enough.
