A method for identifying a computer comprising the steps of: in the course of a first online transaction between a computer and an electronic commerce business: obtaining selected information about the computer during the first online transaction including a local time according to a resident computer clock and at least one non-personal identification parameter; measuring a local server time from a website server clock; calculating a delta of time parameter based upon a difference in time between the local server time and the local time according to the resident computer clock; and generating a first computer identifier to identify the computer that is derived from the delta of time parameter in combination with at least one non-personal identification parameter related to the computer; in the course of a second online transaction between a computer and an electronic commerce business: obtaining selected information about the computer during the second online transaction including a local time according to a resident computer clock and at least one non-personal identification parameter; measuring a local server time from a website server clock; calculating a delta of time parameter based upon a difference in time between the local server time and the local time according to the resident computer clock; and generating a second computer identifier to identify the computer that is derived from the delta of time parameter in combination with at least one non-personal identification parameter related to the computer; flagging the first computer identifier in response to determining the first online transaction may be a fraudulent transaction; comparing, with aid of the processor, the first computer identifier and the second computer identifier; determining, with aid of the processor, that a measured difference between the delta of time parameter of the first computer identifier and the delta of time parameter of the second computer identifier falls within a selected range; and indicating, to the electronic commerce business that the computer was used in the first online transaction and the second online transaction, based at least on the determination that the measured difference falls within the selected range. in the course of a first online transaction between a computer and an electronic commerce business: obtaining selected information about the computer during the first online transaction including a local time according to a resident computer clock and at least one non-personal identification parameter; measuring a local server time from a website server clock; calculating a delta of time parameter based upon a difference in time between the local server time and the local time according to the resident computer clock; and generating a first computer identifier to identify the computer that is derived from the delta of time parameter in combination with at least one non-personal identification parameter related to the computer; obtaining selected information about the computer during the first online transaction including a local time according to a resident computer clock and at least one non-personal identification parameter; measuring a local server time from a website server clock; calculating a delta of time parameter based upon a difference in time between the local server time and the local time according to the resident computer clock; and generating a first computer identifier to identify the computer that is derived from the delta of time parameter in combination with at least one non-personal identification parameter related to the computer; in the course of a second online transaction between a computer and an electronic commerce business: obtaining selected information about the computer during the second online transaction including a local time according to a resident computer clock and at least one non-personal identification parameter; measuring a local server time from a website server clock; calculating a delta of time parameter based upon a difference in time between the local server time and the local time according to the resident computer clock; and generating a second computer identifier to identify the computer that is derived from the delta of time parameter in combination with at least one non-personal identification parameter related to the computer; obtaining selected information about the computer during the second online transaction including a local time according to a resident computer clock and at least one non-personal identification parameter; measuring a local server time from a website server clock; calculating a delta of time parameter based upon a difference in time between the local server time and the local time according to the resident computer clock; and generating a second computer identifier to identify the computer that is derived from the delta of time parameter in combination with at least one non-personal identification parameter related to the computer; flagging the first computer identifier in response to determining the first online transaction may be a fraudulent transaction; comparing, with aid of the processor, the first computer identifier and the second computer identifier; determining, with aid of the processor, that a measured difference between the delta of time parameter of the first computer identifier and the delta of time parameter of the second computer identifier falls within a selected range; and indicating, to the electronic commerce business that the computer was used in the first online transaction and the second online transaction, based at least on the determination that the measured difference falls within the selected range.