Various places. Most often word-of-mouth - a friend visits a place I've never been (and sometimes barely heard of), says it's great, so I want to see it myself. I have some friends with funky / off-the-beaten-path interests, so they usually have good suggestions that aren't going to hit the front page of typical travel/tourist sites.

I have a list of future trips to plan that is probably longer than I'll ever actually get to. For now, I'm prioritizing the ones that can leverage maximum value from miles, points, and status. Later in life, I hope to have greater amounts of disposable cash but less business-travel-driven points/miles/status, and some different types of trips will unfold. Ones that don't involve traditional hotels, commercial airlines, etc.