The invention provides a system and method for automatically displaying a user’s logged-in status across an Internet based network of affiliated Web sites via a visual indicator such as a toolbar to help the user to be certain about his logged-in status when he stays with one or switches from one to another affiliated Web site. The apparatus further comprises a controllable means to vary the resistance to movement of the piston in the chamber, a sensor, and a controller including a timer. Also, a preferred embodiment of the present invention includes, in response to determining the entry exists in the data structure, selecting a peer memory cache out of the collection of memory caches at the same level in the hierarchy to receive the data block from the source memory cache upon eviction. Salt formation of this base with hydrogen chloride gave pharmaceutically acceptable erlotinib hydrochloride of formula with a HPLC purity of >99. A valve allows the liquid to be added and prevents escape of the liquid.