I was stuck there for several hours during a storm, so I wandered around quite a bit.

TIPS:
1. figure out how to use a Japanese payphone before you get into a situation where you MUST make a call (like to tell the person picking you up you’ll be 3 hours late!). they only accept special phone cards or Japanese coins. luckily, i got Japanese coins in change after buying a magazine in US dollars but I couldn’t figure out how much money to put in. the Japanese person using the phone next to mine was no help.
2. you can take a shower or get McD’s there (they have some funky menu variations).
3. get something at the candy/goodies shop!
4. if your plane gets delayed…keep checking to make sure you’re waiting at the right gate because they changed gates on me 3 or 4 times and were very bad about notifying everyone!
5. be patient with the toilets. eventually you’ll find the right buttons (the “flush sound” button was very funny and embarassing).