"While many DSLR users still prefer a good and large traditional optical viewfinder, many are switching to using the LCD monitor for a bigger and more comfortable viewing. Sony has now introduced a 5-in. external LCD monitor that clips onto the accessory shoe of its DSLRs and that offers hi-resolution viewing." Check it out here.
I like that small Sony monitor you found but I wish that article said how much it was going to be (unless I overlooked it)