I've just started building one as well. Going the Raspberry Pi with the iPac2 route for now. I have an LCD but it is too big so will either try another one with some of the tricks mentioned above or will go for a CRT monitor. My goal will be to get old arcade games up on a pub sized cocktail table so I can use the same stools as I have for the pins and pool table - should finish the game room off nicely.