xbox mod chips help

[goldenegg]

is there any site that mods/updates the xbox for you?

and what is the chip called where you can pop in the disc, let it download on to the xbox, and play the game without ever putting in the disc ever again?

and i found this other thing on ebay where it came with nes/snes/gb/gba/sg/smd/n64/other emulators and games programmed into it. whats that called? (yes i know im a total newb)