Penfed has a 5% rewards on gas. The nice thing with them is they credit your rewards immediately each month rather than each year (like Amex Costco).

Like the other posters have said, just stick it in a CD or cash equivalent. After taxes, 100k is maybe 1k. That’s nice, but think how you’d feel if you invested it poorly and now, you can’t even buy a house.

I think Ally used to have a CD that you can tap early as well without penalty, but I don’t rate chase so haven’t been following any of it…

Penfed is generally a decent honest company to deal with I’ve felt so far (yes, I’m a customer).