Japan Airlines ("JAL") miles are very valuable. First, you need to sign up for JAL's Mileage Bank points program.
Points Transfer Partners
You can transfer from Marriott at a 3 (Marriott) to 1 airline point transfer ratio. You can also get an additional 5,000 airline points bonus if you transfer in increments of 60,000 Marriott points. (e.g., 60,000 Marriott points become 25,000 airline points, whereas if you only transfer 59,000 Marriott points, you would only get 19,667 airline points).
- Hyatt (5 to 2)
- IHG (5 to 1)
- Hilton (10 to 1)
Fly with JAL and their Partners
JAL has a points calculator to tell you how many points you would earn flying a specific route.
For OneWorld Partners, you can find each partner here. The earn rate depends on your fare class on each airline.
Credit Card- There is one JAL credit card for the U.S., but I wouldn't recommend it. The sign-up bonus is usually less than 10,000 miles.
Car Rentals- You can earn JAL miles from rental cars, but the rates are only around 300 miles per day outside of Japan and ¥100 for each 1 JAL mile for rentals inside Japan (a $45 rental would net about 500 miles).
Hotel Booking Sites- You can earn points through booking with Hotels.com, Agoda, and Booking.com. However, the rate is only one mile per 200 yen, which would only net you 100 miles on a $185 hotel booking.