The graphics load of a virtual desktop is estimated to determine the capacity of a virtual desktop system. In one embodiment, a portal system that monitors the controlled space includes a radio frequency tag that is attached to inventory and a portal device, which includes a computing device, a receiver and a locking door. A first and a second roller each comprising a plurality of units pick up and successively release of first and the second pieces. Typically the form factors are associated with properties of a display area initiated to present the search results. The methods include various ways for directing a pseudo-conversation with a recipient via a conversation control system.