Text (CF+errata): 1/2. ; {U},{Tap}, Return an artifact you control to its owner's hand: You may put an artifact card from your hand onto the battlefield. [Oracle 2009/07/08]
You can put the same card that was returned to your hand back into play. If you do, it's considered a new copy of that card. [Conflux FAQ 2008/12/16]
It can return itself to your hand, and then be put into play as part of its own effect. [Conflux FAQ 2008/12/16]
Returning an artifact is a cost and it cannot be responded to or interrupted. [Conflux FAQ 2008/12/16]