TV mount corner

I have justed purchased a 42" plasma and plan to mount it in the corner of my living room...best place for it unfortunately. I am going to box the corner out so the tv will sit tight into the corner with the edges of the tv touching the wall at either side.

In doing this i will create a void behind the tv, i would like to house my equipment behind here, space for 3 items would be needed i think. The obvious thing is access with this, i need to be able to safely and securely drop the items down when i want to use the dvd player and then put it back once it is playing the dvd.

Basically all i want to be able to see when in the room is the tv in the corner.

Is there any hydraulic arms on the market that perform such actions??

Any help or advice would be appreciated thanks guys