EGS concept that sprang fully formed into my head yesterday: Somewhere, in another dimension where Earth has magical aliens, there was a girl named Ellen Dunkel and a seyunolu (alien chimera, basically) named Kaoli, who grew up for 17 or 18 years, made a bunch of friends, lived out full lives up through high school ...
... and then suddenly, one day, they disappeared.
Like ... this idea probably doesn't work at all in the current canon, due to the fact that it would require some sort of time travel; otherwise, how would the connection be made with their selves from eighteen years ago, and how could it pause and resume each night? (Although ... Dan's problem was explicitly with changing the past ...) Most likely, it's a recording of some sort, which works on similar principles to Sarah's VR-timestop spell (which is ... somehow ... enough for the purpose of their souls??? Why weren't Elliot's memories enough!?). For that matter, I can't imagine that 2004-2005-era Dan Shive put that much thought into the whole deal (Ellen made friends she'll never see again!), so the second life was just a plot device.
But it's fun to imagine all the possibilities. What if their second-life friends come looking? What if Second Life Mr. and Mrs. Dunkel have the ability to start searching other dimensions, and we learn Stuff™ about their counterparts in the main universe as a result? What if Ellen's Second Life ex-boyfriend Archie becomes plot-relevant!?