A method for communicating using electronic devices, the method comprising: receiving an electronic message and an indication of a sender-specified destination for the electronic message, wherein the sender-specified destination comprises an instant message identity; determining whether the sender-specified destination is available to receive the electronic message using a first mode of communication; determining whether a second destination using a second mode of communication associated with the sender-specified destination is known by the sender, wherein the second destination comprises a mobile telephone number, wherein determining whether a mobile telephone number is known by the sender to be associated with the second destination comprises identifying, in a collection of contact information associated with the sender, a stored association of the mobile telephone number and the instant message identity, wherein determining whether a mobile telephone number is known by the sender to be associated with the second destination further comprises: determining a degree of separation between the sender and an intended recipient associated with the instant message identity, wherein the degree of separation describes a relationship between the sender and the intended recipient; and determining whether the degree of separation between the sender and the intended recipient is within a threshold degree of separation; and in response to a determination that the sender-specified destination is not available and that the second destination using the second mode of communication is known by the sender to be associated with the sender-specified destination, enabling transmission of a communication to the second destination using the second mode of communication, wherein the communication is based on the electronic message. receiving an electronic message and an indication of a sender-specified destination for the electronic message, wherein the sender-specified destination comprises an instant message identity; determining whether the sender-specified destination is available to receive the electronic message using a first mode of communication; determining whether a second destination using a second mode of communication associated with the sender-specified destination is known by the sender, wherein the second destination comprises a mobile telephone number, wherein determining whether a mobile telephone number is known by the sender to be associated with the second destination comprises identifying, in a collection of contact information associated with the sender, a stored association of the mobile telephone number and the instant message identity, wherein determining whether a mobile telephone number is known by the sender to be associated with the second destination further comprises: determining a degree of separation between the sender and an intended recipient associated with the instant message identity, wherein the degree of separation describes a relationship between the sender and the intended recipient; and determining whether the degree of separation between the sender and the intended recipient is within a threshold degree of separation; and determining a degree of separation between the sender and an intended recipient associated with the instant message identity, wherein the degree of separation describes a relationship between the sender and the intended recipient; and determining whether the degree of separation between the sender and the intended recipient is within a threshold degree of separation; and in response to a determination that the sender-specified destination is not available and that the second destination using the second mode of communication is known by the sender to be associated with the sender-specified destination, enabling transmission of a communication to the second destination using the second mode of communication, wherein the communication is based on the electronic message.