I also like

sh int | inc line protocol is|Last input

which outputs

FastEthernet0/29 is down, line protocol is down (notconnect)
  Last input never, output never, output hang never
FastEthernet0/30 is up, line protocol is up (connected)
  Last input never, output 00:00:07, output hang never
FastEthernet0/46 is down, line protocol is down (notconnect)
  Last input never, output 6d23h, output hang never

The output parameter tells you when the port last saw traffic which is useful for identifying those ports that are only occasionally used.

I also like

sh int | inc line protocol is|Last input

which outputs

FastEthernet0/29 is down, line protocol is down (notconnect)
  Last input never, output never, output hang never
FastEthernet0/30 is up, line protocol is up (connected)
  Last input never, output 00:00:07, output hang never
FastEthernet0/46 is down, line protocol is down (notconnect)
  Last input never, output 6d23h, output hang never

The output parameter tells you when the port last saw traffic which is useful for identifying those ports that are only occasionally used.

EDIT: Also worth noting (for reasons beyond the scope of this question) is that "Last input" is almost always "never"