I use RTM for a lot of "I need this but not now" use cases, but one I get a lot of use out of is listing future gifts.

For my wife and my son - they mention something they like, but birthday/Christmas not for a long time? On the list, and I can consult it at the right time.

And actually just as much for me - I'm hard to buy for sometimes, so when I see something I like but I'm not going to get for myself - on the list, and when my wife comes asking for ideas, I'm ready to go!