A vehicle utilization system and method permitting use of vehicles having respective identification codes includes a key having a memory for storing enabling codes enabling use of the vehicles; and an enabling device, in each vehicle, permitting use of the vehicle by a user in possession of the key, if the enabling code stored in the key meets given conditions. The methods including determining whether a threshold number of minutes have been reached during the calling plan period; and incrementally adding minutes to the calling plan when the threshold number of minutes has been reached. Additionally, various chemotherapeutic agent and radiation therapies are described which may be advantageously used in conjunction with electrical therapy to ameliorate cancer. In some embodiments, the word lines of the plurality of blocks define gaps separating each block of the string from neighboring blocks of the string.