Text (CH+errata): 1/1. ; {1}{R}{R},{Tap}: Gain control of target artifact for as long as you control ~this~. [Oracle 2009/07/08]
His ability can take control of more than one artifact, although only one each time the ability is used. [Arab FAQ 1994/01/05]
Any artifact can be taken. This includes artifact creatures, and token creatures (see Rule 110.5) that count as artifacts, such as Wasps from The Hive. [D'Angelo 1994/06/01]
Aladdin's ability does not lose control of a creature if it becomes an invalid target. If the target stops being an artifact, the ability's control effect continues. It only checks the validity of the target on announcement and resolution of his ability. [WotC Rules Team 1995/02/09]
Extended tournaments (see Rule 913) have banned this card since 1999/10/01.
Note - This card was creature type "Aladdin" until Oracle 2007/10/01, when it became "Human Rogue".