Sadly, no digital out. There are some dolby logic games (like RE4) but no digital. Still sounds fine on my Axioms though!
There is a component cable available, but my understanding is that the newer runs of GC's don't have that port anymore. The component cable is hard to come by, I got mine on nintendo.com. W/ component, it looks GREAT on my plasma.
Granted, the game library isn't as big as PS2 or the XBOX, but where else are you going to find the Mario franchise?
My personal GC favs are (no particular order)
1) Pikmin 1 and 2
2) Resident Evil 0, 1 and 4
3) Zelda the Wind Waker
4) Eternal Darkness (fantastic concept IMHO)
5) Mario Kart
Go here if for some GC specific info:
Cube Your Enthusiasm 
