No, it's not a background actor from the set of Transformers 3, it's the latest perk giving to the new star of Two and a Half Men by his new employers, in the form of a giant 2-story "mobile estate". This beast was created by Anderson Mobile Estates, costing the show around $35,000 a month. Anderson Mobile Estates, as their name suggests, goes way beyond your typical mobile home or trailer, only specializing in high-end, custom transport, supplying other big stars such as Will Smith, Maria Carey, Jennifer Lopez, Vin Diesel and Ice Cube.
The model bestowed to Ashton is called Baby Girl, popular with celebrity clientele, it covers 1,100 sq feet, 53 feet long, 15 feet high and weighs in at 30 tons. It features seven 3D plasma screens, satellite TV, a high-end security system and two bathrooms. The second floor and the side sections are also hydraulically controlled, so they can be retracted before moving. The furniture is all custom-made as well, with pieces that fold up when the second floor and side compartments retract. The whole thing is controlled by remote control, which I imagine has to expand hydraulically just to fit enough buttons to operate it all.
Buying one would set you back around $2 million, or at Ashton's new $700,000 per episode salary, only about two and a half episodes.