I thought it would be nice to have a post where we could keep track of all the various miles, rewards, and points programs and when/if their miles/points expire (and if so, how quickly) - I'm sure we all have many, many rewards memberships, and sometimes these things are hard to keep track of. I'll start off, and feel free to add (I can always edit the post to make additions). I'd especially appreciate additions for other airlines, as I'm very loyal to Delta (due to a ridiculous number of unfortunate experiences on literally every other airline)

Non-Expiring Points/Miles
-Skymiles

Expiring (+ activity that "resets" expiration date)
-Starwood Starpoints (1 year, resettable by staying at a property)
-Marriott (1 year?)
-Amtrak Guest Rewards (3(?), resettable by any activity)
-Wyndham Rewards (18 months resettable by any activity; 4 years "hard" expiration)
-AA (18 months, resettable by any activity)
-UA (18 months, resettable by any activity)
-LAN (3 years "hard" expiration)