In a similar vein to this, I've taken to trying to rope friends into taking even a medium distance run on a train with me, and/or offering to try and sync up travel plans...in no small part because there's something to be gained from a day or two where you can just shoot the bull without much interference. This is also part of why we go on vacations together...with a lot of my friends, we've regularly had long, long conversations over the years.