things to do in NRT T1 to kill 5 hours?

I have 5 hours to kill between transfer at NRT T1 in the afternoon.

for transfer – i actually need to go through immigration / pick up luggage / then get ticket at different airline / pass security and go to the gate.

any suggestions?

not sure if there's much do to unless you check in / pass security, maybe more things to do as you walk to the gates?

i'd imagine just checking out all convenient stores, maybe some inexpensive restaurant for food. what else?