The Reality Chip

Legendary Artifact Creature — Equipment Jellyfish{1}{U}0/4

You may look at the top card of your library any time. As long as The Reality Chip is attached to a creature, you may play lands and cast spells from the top of your library. Reconfigure {2}{U} ({2}{U}: Attach to target creature you control; or unattach from a creature. Reconfigure only as a sorcery. While attached, this isn't a creature.)

Colour identity Blue · Reconfigure · Commander page

In short

The Reality Chip has 5 listed printings; the most valuable is the Showcase printing from NEO at US$8.08 on TCGplayer's market price. Prices below are the cheapest in-stock listing in the United States.